Relación 4
De Lógica matemática y fundamentos (2017-18)
Revisión del 16:18 22 mar 2018 de Carmarria (discusión | contribuciones)
chapter {* R4: Deducción natural proposicional *}
theory R4
imports Main
begin
text {*
---------------------------------------------------------------------
El objetivo de esta relación es demostrar cada uno de los ejercicios
usando sólo las reglas básicas de deducción natural de la lógica
proposicional (sin usar el método auto).
Las reglas básicas de la deducción natural son las siguientes:
· conjI: ⟦P; Q⟧ ⟹ P ∧ Q
· conjunct1: P ∧ Q ⟹ P
· conjunct2: P ∧ Q ⟹ Q
· notnotD: ¬¬ P ⟹ P
· notnotI: P ⟹ ¬¬ P
· mp: ⟦P ⟶ Q; P⟧ ⟹ Q
· mt: ⟦F ⟶ G; ¬G⟧ ⟹ ¬F
· impI: (P ⟹ Q) ⟹ P ⟶ Q
· disjI1: P ⟹ P ∨ Q
· disjI2: Q ⟹ P ∨ Q
· disjE: ⟦P ∨ Q; P ⟹ R; Q ⟹ R⟧ ⟹ R
· FalseE: False ⟹ P
· notE: ⟦¬P; P⟧ ⟹ R
· notI: (P ⟹ False) ⟹ ¬P
· iffI: ⟦P ⟹ Q; Q ⟹ P⟧ ⟹ P = Q
· iffD1: ⟦Q = P; Q⟧ ⟹ P
· iffD2: ⟦P = Q; Q⟧ ⟹ P
· ccontr: (¬P ⟹ False) ⟹ P
---------------------------------------------------------------------
*}
text {*
Se usarán las reglas notnotI y mt que demostramos a continuación. *}
lemma notnotI: "P ⟹ ¬¬ P"
by auto
lemma mt: "⟦F ⟶ G; ¬G⟧ ⟹ ¬F"
by auto
section {* Implicaciones *}
text {* ---------------------------------------------------------------
Ejercicio 1. Demostrar
p ⟶ q, p ⊢ q
------------------------------------------------------------------ *}
lemma ejercicio_1: josrodjim2 carmarria inmbenber marmedmar3
assumes 1: "p ⟶ q" and
2: "p"
shows "q"
proof -
show 1: "q" using 1 2 by (rule mp)
qed
lemma ej_1: joslopjim4
assumes "p --> q"
"p"
shows "q"
proof -
show "q" using assms(1) assms(2) by (rule mp)
qed
text {* ---------------------------------------------------------------
Ejercicio 2. Demostrar
p ⟶ q, q ⟶ r, p ⊢ r
------------------------------------------------------------------ *}
lemma ejercicio_2: josrodjim2 carmarria inmbenber marmedmar3
assumes 1: "p ⟶ q" and
2: "q ⟶ r" and
3: "p"
shows "r"
proof-
have 4: "q" using 1 3 by (rule mp)
show "r" using 2 4 by (rule mp)
qed
lemma ej_2: joslopjim4
assumes "p ⟶ q"
"q ⟶ r"
"p"
shows "r"
proof -
have "q" using `p⟶q` `p` by (rule mp)
show "r" using `q⟶r` `q` by (rule mp)
qed
text {* ---------------------------------------------------------------
Ejercicio 3. Demostrar
p ⟶ (q ⟶ r), p ⟶ q, p ⊢ r
------------------------------------------------------------------ *}
lemma ejercicio_3: josrodjim2 carmarria inmbenber marmedmar3
assumes 1: "p ⟶ (q ⟶ r)" and
2: "p ⟶ q" and
3: "p"
shows "r"
proof-
have 4: "q" using 2 3 by (rule mp)
have 5: "(q ⟶ r)" using 1 3 by (rule mp)
show "r" using 5 4 by (rule mp)
qed
lemma ej_3: joslopjim4
assumes "p ⟶ (q ⟶ r)"
"p ⟶ q"
"p"
shows "r"
proof -
have "q" using `p⟶q` `p` by (rule mp)
have "q⟶r" using `p ⟶ (q ⟶ r)` `p` by (rule mp)
show "r" using `q⟶r` `q` by (rule mp)
qed
text {* ---------------------------------------------------------------
Ejercicio 4. Demostrar
p ⟶ q, q ⟶ r ⊢ p ⟶ r
------------------------------------------------------------------ *}
lemma ejercicio_4: josrodjim2
assumes 1: "p ⟶ q" and
2: "q ⟶ r"
shows "p ⟶ r"
proof-
{ assume 3: "p"
have 4: "q" using 1 3 by (rule mp)
have 5: "r" using 2 4 by (rule mp)}
hence 6: "p ⟶ r" using 3 5 by (rule impI)
show "p⟶r" using 6 by this
oops
lemma ejercicio_4: carmarria
assumes 1: "p ⟶ q" and
2: "q ⟶ r"
shows "p ⟶ r"
proof -
{ assume 3: p
have 4: "q" using 1 3 by (rule mp)
have 5: "r" using 2 4 by (rule mp)
}
thus "p ⟶ r" by (rule impI)
qed
lemma ejercicio_4: inmbenber
assumes 1: "p ⟶ q" and
2: "q ⟶ r"
shows "p ⟶ r"
proof -
{ assume 3: "p"
have 4: "q" using 1 3 by (rule mp)
have 5: "r" using 2 4 by (rule mp) }
thus "p ⟶ r" by (rule impI)
qed
lemma ejercicio_4:marmedmar3
assumes "p ⟶ q"
"q ⟶ r"
shows "p ⟶ r"
proof
assume "p"
with assms(1) have "q" by (rule mp)
with assms(2) show "r" by (rule mp)
qed
lemma ej_4: joslopjim4
assumes "p ⟶ q"
"q ⟶ r"
shows "p ⟶ r"
proof (rule impI)
assume "p"
have "q" using assms(1) `p` by (rule mp)
show "r" using assms(2) `q` by (rule mp)
qed
text {* ---------------------------------------------------------------
Ejercicio 5. Demostrar
p ⟶ (q ⟶ r) ⊢ q ⟶ (p ⟶ r)
------------------------------------------------------------------ *}
lemma ejercicio_5: josrodjim2 (NO DA ERROR, PERO SI ALERTA)
assumes "p ⟶ (q ⟶ r)"
shows "q ⟶ (p ⟶ r)"
proof -
{ assume 2: "q"
{assume 3: "p"
have 4: "q ⟶r" using 1 3 by (rule mp)
have 5: "r" using 4 2 by (rule mp)}
hence 6: "p⟶r" using 3 5 by (rule impI)}
hence 7: "q ⟶ (p ⟶ r)" using 2 6 by (rule impI)
show "q ⟶ (p ⟶ r)" using 7 by this
oops
lemma ejercicio_5: carmarria
assumes 1: "p ⟶ (q ⟶ r)"
shows "q ⟶ (p ⟶ r)"
proof -
{assume 2: q
{assume 3: p
have 4: "q ⟶ r" using 1 3 by (rule mp)
have 5: "r" using 4 2 by (rule mp)
}
hence " p ⟶ r" by (rule impI)
}
thus "q ⟶ (p ⟶ r)" by (rule impI)
qed
lemma ejercicio_5: inmbenber
assumes 1: "p ⟶ (q ⟶ r)"
shows "q ⟶ (p ⟶ r)"
proof -
{assume 2: "q"
{assume 3: "p"
have 4: "q ⟶ r" using 1 3 by (rule mp)
have 5: "r" using 4 2 by (rule mp) }
hence " p ⟶ r" by (rule impI) }
thus "q ⟶ (p ⟶ r)" by (rule impI)
qed
lemma ejercicio_5: marmedmar3
assumes "p ⟶ (q ⟶ r)"
shows "q ⟶ (p ⟶ r)"
proof
assume "q"
show "(p ⟶ r)"
proof
assume "p"
with assms(1) have "(q ⟶ r)" by (rule mp)
thus "r" using `q` by (rule mp)
qed
qed
lemma ej_5: joslopjim4
assumes "p ⟶ (q ⟶ r)"
shows "q ⟶ (p ⟶ r)"
proof (rule impI)
assume "q"
show "p⟶r"
proof (rule impI)
assume "p"
have "q⟶r" using `p ⟶ (q ⟶ r)` `p` by (rule mp)
show "r" using `q⟶r` `q` by (rule mp)
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 6. Demostrar
p ⟶ (q ⟶ r) ⊢ (p ⟶ q) ⟶ (p ⟶ r)
------------------------------------------------------------------ *}
lemma ejercicio_6:josrodjim2
assumes 1: "p ⟶ (q ⟶ r)"
shows "(p ⟶ q) ⟶ (p ⟶ r)"
proof-
{assume 2: "p⟶q"
{assume 3: "p"
have 4: "q⟶r" using 1 3 by (rule mp)
have 5: "q" using 2 3 by (rule mp)
have 6: "r" using 4 5 by (rule mp)}
hence 7: "p⟶r" using 3 6 by (rule impI)}
hence 8: "(p ⟶ q) ⟶ (p ⟶ r)" using 2 7 by (rule impI)
show "(p ⟶ q) ⟶ (p ⟶ r)" using 8 by this
oops
lemma ejercicio_6: carmarria, inmbenber
assumes 1: "p ⟶ (q ⟶ r)"
shows "(p ⟶ q) ⟶ (p ⟶ r)"
proof -
{assume 2: "p ⟶ q"
{assume 3: "p"
have 4: "q" using 2 3 by (rule mp)
have 5: "q ⟶ r" using 1 3 by (rule mp)
have 6: "r" using 5 4 by (rule mp)
}
hence 7: "p ⟶ r" by (rule impI)
}
thus "(p ⟶ q) ⟶ (p ⟶ r)" by (rule impI)
qed
lemma ejercicio_6:marmedmar3
assumes 1: "p ⟶ (q ⟶ r)"
shows "(p ⟶ q) ⟶ (p ⟶ r)"
proof
assume 2: "(p ⟶ q)"
show "(p ⟶ r)"
proof
assume 3: "p"
have 4: "q" using 2 3 by (rule mp)
have 5: "(q ⟶ r)" using 1 3 by (rule mp)
show "r" using 5 4 by (rule mp)
qed
qed
lemma ej_6: joslopjim4
assumes "p ⟶ (q ⟶ r)"
shows "(p ⟶ q) ⟶ (p ⟶ r)"
proof (rule impI)
assume "(p⟶q)"
show "p⟶r"
proof (rule impI)
assume "p"
have "q⟶r" using `p ⟶ (q ⟶ r)` `p` by (rule mp)
have "q" using `p⟶q` `p` by (rule mp)
show "r" using `q⟶r` `q` by (rule mp)
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 7. Demostrar
p ⊢ q ⟶ p
------------------------------------------------------------------ *}
lemma ejercicio_7: (NO SE QUE ESTA MAL)
assumes "p"
shows "q ⟶ p"
proof -
{ assume 2: "q"
have 3: "p" using 1
}
hence 4: "q⟶p" using 2 3 by (rule impI)
show "q⟶p" using 4 by this
oops
lemma ejercicio_7: carmarria, inmbenber
assumes 1: "p"
shows "q ⟶ p"
proof -
{assume 2: "q"
have 3: "p" using 1 by this}
thus "q ⟶ p" by (rule impI)
qed
lemma ejercicio_7:marmedmar3
assumes "p"
shows "q ⟶ p"
proof
assume "q"
show "p" using assms(1) by this
qed
lemma ej_7: joslopjim4
assumes "p"
shows "q ⟶ p"
proof (rule impI)
assume "q"
show "p" using assms by this
qed
text {* ---------------------------------------------------------------
Ejercicio 8. Demostrar
⊢ p ⟶ (q ⟶ p)
------------------------------------------------------------------ *}
lemma ejercicio_8: carmarria
"p ⟶ (q ⟶ p)"
proof -
{assume 1: p
{assume 2: q
have 3: p using 1 by this
}
hence 4: "q ⟶ p" by (rule impI)
}
thus "p ⟶ (q ⟶ p)" by (rule impI)
qed
lemma ejercicio_8: marmedmar3
"p ⟶ (q ⟶ p)"
proof
assume 1: "p"
show "(q ⟶ p)"
proof
assume 2: "q"
show "p" using 1 by this
qed
qed
lemma ej_8: joslopjim4
shows "p⟶(q⟶p)"
proof (rule impI)
assume "p"
show "q⟶p"
proof (rule impI)
assume "q"
show "p" using `p` by this
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 9. Demostrar
p ⟶ q ⊢ (q ⟶ r) ⟶ (p ⟶ r)
------------------------------------------------------------------ *}
lemma ejercicio_9: carmarria
assumes 1: "p ⟶ q"
shows "(q ⟶ r) ⟶ (p ⟶ r)"
proof -
{assume 2: "q ⟶ r"
{assume 3: "p"
have 4: "q" using 1 3 by (rule mp)
have 5: "r" using 2 4 by (rule mp)
}
hence 6: "p ⟶ r" by (rule impI)
}
thus 7: "(q ⟶ r) ⟶ (p ⟶ r)" by (rule impI)
qed
lemma ejercicio_9: marmedmar3
assumes "p ⟶ q"
shows "(q ⟶ r) ⟶ (p ⟶ r)"
proof
assume "(q ⟶ r)"
show "(p ⟶ r)"
proof
assume "p"
with `(p ⟶ q)` have "q" by (rule mp)
with `(q ⟶ r)` show "r" by (rule mp)
qed
qed
lemma ej_9: joslopjim4
assumes "p ⟶ q"
shows "(q ⟶ r) ⟶ (p ⟶ r)"
proof (rule impI)
assume "q⟶r"
show "p⟶r"
proof (rule impI)
assume "p"
have "q" using `p⟶q` `p` by (rule mp)
show "r" using `q⟶r` `q` by (rule mp)
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 10. Demostrar
p ⟶ (q ⟶ (r ⟶ s)) ⊢ r ⟶ (q ⟶ (p ⟶ s))
------------------------------------------------------------------ *}
lemma ejercicio_10: carmarria
assumes 1: "p ⟶ (q ⟶ (r ⟶ s))"
shows "r ⟶ (q ⟶ (p ⟶ s))"
proof-
{assume 2: r
{assume 3: q
{assume 4: p
have 5: "q ⟶ (r ⟶ s)" using 1 4 by (rule mp)
have 6: "r ⟶ s" using 5 3 by (rule mp)
have 7: s using 6 2 by (rule mp)
}
hence 8: "p ⟶ s" by (rule impI)
}
hence 9: "q ⟶ (p ⟶ s)" by (rule impI)
}
thus "r ⟶ (q ⟶ (p ⟶ s))" by (rule impI)
qed
lemma ejercicio_10: marmedmar3
assumes 1: "p ⟶ (q ⟶ (r ⟶ s))"
shows "r ⟶ (q ⟶ (p ⟶ s))"
proof
assume 2: "r"
show "(q ⟶ (p ⟶ s))"
proof
assume 3: "q"
show "(p ⟶ s)"
proof
assume 4: "p"
have 5: "(q ⟶ (r ⟶ s))" using 1 4 by (rule mp)
have 6: "(r ⟶ s)" using 5 3 by (rule mp)
show "s" using 6 2 by (rule mp)
qed
qed
qed
lemma ej_10: joslopjim4
assumes "p ⟶ (q ⟶ (r ⟶ s))"
shows "r ⟶ (q ⟶ (p ⟶ s))"
proof (rule impI)
assume "r"
show "q⟶(p⟶s)"
proof (rule impI)
assume "q"
show "p⟶s"
proof (rule impI)
assume "p"
have "q ⟶ (r ⟶ s)" using `p ⟶ (q ⟶ (r ⟶ s))` `p` by (rule mp)
have "r⟶s" using `q ⟶ (r ⟶ s)` `q` by (rule mp)
show "s" using `r-->s` `r` by (rule mp)
qed
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 11. Demostrar
⊢ (p ⟶ (q ⟶ r)) ⟶ ((p ⟶ q) ⟶ (p ⟶ r))
------------------------------------------------------------------ *}
lemma ejercicio_11: carmarria
"(p ⟶ (q ⟶ r)) ⟶ ((p ⟶ q) ⟶ (p ⟶ r))"
proof -
{assume 1: "p ⟶ (q ⟶ r)"
{assume 2: "p ⟶ q"
{assume 3: p
have 4: q using 2 3 by (rule mp)
have 5: "q ⟶ r" using 1 3 by (rule mp)
have 6: r using 5 4 by (rule mp)
}
hence 7: "p ⟶ r" by (rule impI)
}
hence 8: "(p ⟶ q) ⟶ (p ⟶ r)" by (rule impI)
}
thus "(p ⟶ (q ⟶ r)) ⟶ ((p ⟶ q) ⟶ (p ⟶ r))" by (rule impI)
qed
lemma ejercicio_11: marmedmar3
"(p ⟶ (q ⟶ r)) ⟶ ((p ⟶ q) ⟶ (p ⟶ r))"
proof
assume 1: "(p ⟶ (q ⟶ r))"
show "((p ⟶ q) ⟶ (p ⟶ r))"
proof
assume 2: "(p ⟶ q)"
show "(p ⟶ r)"
proof
assume 3: "p"
have 4: "(q ⟶ r)" using 1 3 by (rule mp)
have 5: "q" using 2 3 by (rule mp)
show "r" using 4 5 by (rule mp)
qed
qed
qed
lemma ej_11: joslopjim4
shows "(p ⟶ (q ⟶ r)) ⟶ ((p ⟶ q) ⟶ (p ⟶ r))"
proof (rule impI)
assume "p⟶(q⟶r)"
show "(p⟶q)⟶(p⟶r)"
proof (rule impI)
assume "p⟶q"
show "p⟶r"
proof (rule impI)
assume "p"
have "q" using `p⟶q` `p` by (rule mp)
have "q⟶r" using `p⟶(q⟶r)` `p` by (rule mp)
show "r" using `q⟶r` `q` by (rule mp)
qed
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 12. Demostrar
(p ⟶ q) ⟶ r ⊢ p ⟶ (q ⟶ r)
------------------------------------------------------------------ *}
lemma ejercicio_12: carmarria
assumes 1: "(p ⟶ q) ⟶ r"
shows "p ⟶ (q ⟶ r)"
proof -
{assume 2: p
{assume 3: q
{assume 4: p
have 5: q using 3 by this
}
hence 6: "p ⟶ q" by (rule impI)
have 7: r using 1 6 by (rule mp)
}
hence 8: "q ⟶ r" by (rule impI)
}
thus "p ⟶ (q ⟶ r)" by (rule impI)
qed
lemma ej_12: joslopjim4
assumes "(p ⟶ q) ⟶ r"
shows "p ⟶ (q ⟶ r)"
proof (rule impI)
assume "p"
show "q⟶r"
proof (rule impI)
assume "q"
have "p⟶q"
proof (rule impI)
assume "p"
show "q" using `q` by this
qed
show "r" using `(p ⟶ q) ⟶ r` `p⟶q` by (rule mp)
qed
qed
section {* Conjunciones *}
text {* ---------------------------------------------------------------
Ejercicio 13. Demostrar
p, q ⊢ p ∧ q
------------------------------------------------------------------ *}
lemma ejercicio_13: carmarria marmedmar3
assumes "p"
"q"
shows "p ∧ q"
proof-
show "p \<and> q" using assms(1) assms(2) by (rule conjI)
qed
lemma ej_13: joslopjim4
assumes "p"
"q"
shows "p ∧ q"
proof-
show "p∧q" using `p` `q` by (rule conjI)
qed
text {* ---------------------------------------------------------------
Ejercicio 14. Demostrar
p ∧ q ⊢ p
------------------------------------------------------------------ *}
lemma ejercicio_14: carmarria marmedmar3
assumes "p ∧ q"
shows "p"
proof -
show "p" using assms by (rule conjunct1)
qed
lemma ej_14: joslopjim4
assumes "p ∧ q"
shows "p"
proof -
show "p" using assms by (rule conjunct1)
qed
text {* ---------------------------------------------------------------
Ejercicio 15. Demostrar
p ∧ q ⊢ q
------------------------------------------------------------------ *}
lemma ejercicio_15: carmarria marmedmar3
assumes "p ∧ q"
shows "q"
proof -
show q using assms(1) by (rule conjunct2)
qed
lemma ej_15: joslopjim4
assumes "p ∧ q"
shows "q"
proof-
show "q" using assms by (rule conjunct2)
qed
text {* ---------------------------------------------------------------
Ejercicio 16. Demostrar
p ∧ (q ∧ r) ⊢ (p ∧ q) ∧ r
------------------------------------------------------------------ *}
lemma ejercicio_16: carmarria marmedmar3
assumes 1: "p ∧ (q ∧ r)"
shows "(p ∧ q) ∧ r"
proof -
have 2: "q \<and> r" using 1 by (rule conjunct2)
have 3: p using 1 by (rule conjunct1)
have 4: q using 2 by (rule conjunct1)
have 5: r using 2 by (rule conjunct2)
have 6: "p \<and> q" using 3 4 by (rule conjI)
show "(p \<and> q) \<and> r" using 6 5 by (rule conjI)
qed
lemma ej_16: joslopjim4
assumes "p ∧ (q ∧ r)"
shows "(p ∧ q) ∧ r"
proof-
have "p" using assms by (rule conjunct1)
have "q∧r" using assms by (rule conjunct2)
have "q" using `q∧r` by (rule conjunct1)
have "r" using `q∧r` by (rule conjunct2)
have "p∧q" using `p` `q` by (rule conjI)
show "(p∧q)∧r" using `p∧q` `r` by (rule conjI)
qed
text {* ---------------------------------------------------------------
Ejercicio 17. Demostrar
(p ∧ q) ∧ r ⊢ p ∧ (q ∧ r)
------------------------------------------------------------------ *}
lemma ejercicio_17:
assumes "(p ∧ q) ∧ r"
shows "p ∧ (q ∧ r)"
proof (rule conjI)
have "p ∧ q" using assms ..
thus "p" ..
next
show "q ∧ r"
proof (rule conjI)
have "p ∧ q" using assms ..
thus "q" ..
next
show "r" using assms ..
qed
qed
lemma ejercicio_17: carmarria marmedmar3
assumes 1:"(p ∧ q) ∧ r"
shows "p ∧ (q ∧ r)"
proof-
have 2:"p \<and> q" using 1 by (rule conjunct1)
have 3: r using 1 by (rule conjunct2)
have 4: p using 2 by (rule conjunct1)
have 5: q using 2 by (rule conjunct2)
have 6: "q \<and> r" using 5 3 by (rule conjI)
show "p \<and> (q \<and> r)" using 4 6 by (rule conjI)
qed
lemma ej_17: joslopjim4
assumes "(p ∧ q) ∧ r"
shows "p ∧ (q ∧ r)"
proof-
have "p∧q" using assms by (rule conjunct1)
have "r" using assms by (rule conjunct2)
have "p" using `p∧q` by (rule conjunct1)
have "q" using `p∧q` by (rule conjunct2)
have "q∧r" using `q` `r` by (rule conjI)
show "p∧(q∧r)" using `p` `q∧r` by (rule conjI)
qed
text {* ---------------------------------------------------------------
Ejercicio 18. Demostrar
p ∧ q ⊢ p ⟶ q
------------------------------------------------------------------ *}
lemma ejercicio_18: carmarria
assumes "p ∧ q"
shows "p ⟶ q"
proof -
{assume p
have q using assms(1) by (rule conjunct2)
}
thus "p ⟶ q" by (rule impI)
qed
lemma ejercicio_18: marmedmar3
assumes "p ∧ q"
shows "p ⟶ q"
proof
assume "p"
show "q" using assms by (rule conjunct2)
qed
lemma ej_18: joslopjim4
assumes "p ∧ q"
shows "p ⟶ q"
proof (rule impI)
assume "p"
show "q" using assms by (rule conjunct2)
qed
text {* ---------------------------------------------------------------
Ejercicio 19. Demostrar
(p ⟶ q) ∧ (p ⟶ r) ⊢ p ⟶ q ∧ r
------------------------------------------------------------------ *}
lemma ejercicio_19: carmarria
assumes 1: "(p ⟶ q) ∧ (p ⟶ r)"
shows "p ⟶ q ∧ r"
proof -
{assume 2: p
have 3: "p ⟶ q" using 1 by (rule conjunct1)
have 4: "p ⟶ r" using 1 by (rule conjunct2)
have 5: q using 3 2 by (rule mp)
have 6: r using 4 2 by (rule mp)
have 7: "q \<and> r" using 5 6 by (rule conjI)
}
thus "p ⟶ q \<and> r" by (rule impI)
qed
lemma ejercicio_19: marmedmar3
assumes 1: "(p ⟶ q) ∧ (p ⟶ r)"
shows "p ⟶ q ∧ r"
proof
have 2: "(p ⟶ q)" using assms by (rule conjunct1)
have 3: "(p ⟶ r)" using assms by (rule conjunct2)
assume 4: "p"
with `(p ⟶ q)` have 5: "q" by (rule mp)
have 6: "r" using 3 4 by (rule mp)
show "q ∧ r" using 5 6 by (rule conjI)
qed
lemma ej_19: joslopjim4
assumes "(p ⟶ q) ∧ (p ⟶ r)"
shows "p ⟶ q ∧ r"
proof (rule impI)
assume "p"
have "p⟶q" using assms by (rule conjunct1)
have "q" using `p⟶q` `p` by (rule mp)
have "p⟶r" using assms by (rule conjunct2)
have "r" using `p⟶r` `p` by (rule mp)
show "q∧r" using `q` `r` by (rule conjI)
qed
text {* ---------------------------------------------------------------
Ejercicio 20. Demostrar
p ⟶ q ∧ r ⊢ (p ⟶ q) ∧ (p ⟶ r)
------------------------------------------------------------------ *}
lemma ejercicio_20: carmarria
assumes 1: "p ⟶ q ∧ r"
shows "(p ⟶ q) ∧ (p ⟶ r)"
proof -
{assume 2: p
have 3: "q \<and> r" using 1 2 by (rule mp)
have 4: q using 3 by (rule conjunct1)
}
hence 5: "p ⟶ q" by (rule impI)
{assume 6: p
have 7: "q \<and> r" using 1 6 by (rule mp)
have 8: r using 7 by (rule conjunct2)
}
hence 9: "p ⟶ r" by (rule impI)
show "(p ⟶ q) \<and> (p ⟶ r)" using 5 9 by (rule conjI)
qed
lemma ej_20: joslopjim4
assumes "p ⟶ q ∧ r"
shows "(p ⟶ q) ∧ (p ⟶ r)"
proof-
have "p⟶q"
proof
assume "p"
have "q∧r" using assms `p` by (rule mp)
show "q" using `q∧r` by (rule conjunct1)
qed
have "p⟶r"
proof
assume "p"
have "q∧r" using assms `p` by (rule mp)
show "r" using `q∧r` by (rule conjunct2)
qed
show "(p⟶q)∧(p⟶r)" using `p⟶q` `p⟶r` by (rule conjI)
qed
text {* ---------------------------------------------------------------
Ejercicio 21. Demostrar
p ⟶ (q ⟶ r) ⊢ p ∧ q ⟶ r
------------------------------------------------------------------ *}
lemma ejercicio_21: carmarria
assumes 1: "p ⟶ (q ⟶ r)"
shows "p ∧ q ⟶ r"
proof -
{assume 2: "p \<and> q"
have 3: p using 2 by (rule conjunct1)
have 4: q using 2 by (rule conjunct2)
have 5: "q ⟶ r" using 1 3 by (rule mp)
have 6: r using 5 4 by (rule mp)
}
thus "p ∧ q ⟶ r" by (rule impI)
qed
lemma ejercicio_21: marmedmar3
assumes "p ⟶ (q ⟶ r)"
shows "p ∧ q ⟶ r"
proof
assume "p ∧ q"
hence "p" by (rule conjunct1)
with assms have "(q ⟶ r)" by (rule mp)
have "q" using `p ∧ q` by (rule conjunct2)
with `(q ⟶ r)` show "r" by (rule mp)
qed
lemma ej_21: joslopjim4
assumes "p ⟶ (q ⟶ r)"
shows "p ∧ q ⟶ r"
proof (rule impI)
assume "p∧q"
have "p" using `p∧q` by (rule conjunct1)
have "q" using `p∧q` by (rule conjunct2)
have "q⟶r" using assms `p` by (rule mp)
show "r" using `q⟶r` `q` by (rule mp)
qed
text {* ---------------------------------------------------------------
Ejercicio 22. Demostrar
p ∧ q ⟶ r ⊢ p ⟶ (q ⟶ r)
------------------------------------------------------------------ *}
lemma ejercicio_22: carmarria
assumes "p ∧ q ⟶ r"
shows "p ⟶ (q ⟶ r)"
proof -
{assume p
{assume q
have "p \<and> q" using `p` `q` by (rule conjI)
have r using assms(1) `p \<and> q` by (rule mp)
}
hence "q ⟶ r" by (rule impI)
}
thus "p ⟶ (q ⟶ r)" by (rule impI)
qed
lemma ejercicio_22: marmedmar3
assumes "p ∧ q ⟶ r"
shows "p ⟶ (q ⟶ r)"
proof
assume "p"
show "(q ⟶ r)"
proof
assume "q"
with `p` have "p ∧ q" by (rule conjI)
with assms show "r" by (rule mp)
qed
qed
lemma ej_22: joslopjim4
assumes "p ∧ q ⟶ r"
shows "p ⟶ (q ⟶ r)"
proof (rule impI)
assume "p"
show "q⟶r"
proof (rule impI)
assume "q"
have "p∧q" using `p` `q` by (rule conjI)
show "r" using assms `p∧q` by (rule mp)
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 23. Demostrar
(p ⟶ q) ⟶ r ⊢ p ∧ q ⟶ r
------------------------------------------------------------------ *}
lemma ejercicio_23: carmarria
assumes "(p ⟶ q) ⟶ r"
shows "p ∧ q ⟶ r"
proof -
{assume "p \<and> q"
{assume p
have q using `p \<and> q` by (rule conjunct2)
}
hence "p ⟶ q" by (rule impI)
have r using assms(1) `p ⟶ q` by (rule mp)
}
thus "p \<and> q ⟶ r" by (rule impI)
qed
lemma ejercicio_23: marmedmar3
assumes "(p ⟶ q) ⟶ r"
shows "p ∧ q ⟶ r"
proof
assume "p ∧ q"
have "p" using `p ∧ q` by (rule conjunct1)
have "q" using `p ∧ q` by (rule conjunct2)
hence "(p ⟶ q)" by (rule impI)
with assms show "r" by (rule mp)
qed
lemma ej_23: joslopjim4
assumes "(p ⟶ q) ⟶ r"
shows "p ∧ q ⟶ r"
proof (rule impI)
assume "p∧q"
have "p⟶q"
proof
assume "p"
show "q" using `p∧q` by (rule conjunct2)
qed
show "r" using assms `p⟶q` by (rule mp)
qed
text {* ---------------------------------------------------------------
Ejercicio 24. Demostrar
p ∧ (q ⟶ r) ⊢ (p ⟶ q) ⟶ r
------------------------------------------------------------------ *}
lemma ejercicio_24: carmarria
assumes 1: "p ∧ (q ⟶ r)"
shows "(p ⟶ q) ⟶ r"
proof -
{assume 2: "p ⟶ q"
have 3: p using 1 by (rule conjunct1)
have 4: "q ⟶ r" using 1 by (rule conjunct2)
have 5: q using 2 3 by (rule mp)
have 6: r using 4 5 by (rule mp)
}
thus "(p ⟶ q) ⟶ r" by (rule impI)
qed
lemma ejercicio_24: marmedmar3
assumes "p ∧ (q ⟶ r)"
shows "(p ⟶ q) ⟶ r"
proof
assume "(p ⟶ q)"
have "(q ⟶ r)" using assms by (rule conjunct2)
have "p" using assms by (rule conjunct1)
with `(p ⟶ q)` have "q" by (rule mp)
with `(q ⟶ r)` show "r" by (rule mp)
qed
lemma ej_24: joslopjim4
assumes "p ∧ (q ⟶ r)"
shows "(p ⟶ q) ⟶ r"
proof (rule impI)
assume "p⟶q"
have "p" using assms by (rule conjunct1)
have "q⟶r" using assms by (rule conjunct2)
have "q" using `p⟶q` `p` by (rule mp)
show "r" using `q⟶r` `q` by (rule mp)
qed
section {* Disyunciones *}
text {* ---------------------------------------------------------------
Ejercicio 25. Demostrar
p ⊢ p ∨ q
------------------------------------------------------------------ *}
lemma ejercicio_25: carmarria
assumes "p"
shows "p ∨ q"
proof -
show "p | q" using assms(1) by (rule disjI1)
qed
lemma ej_25: joslopjim4
assumes "p"
shows "p ∨ q"
proof (rule disjI1)
show "p" using assms by this
qed
text {* ---------------------------------------------------------------
Ejercicio 26. Demostrar
q ⊢ p ∨ q
------------------------------------------------------------------ *}
lemma ejercicio_26: carmarria
assumes "q"
shows "p ∨ q"
proof -
show "p | q" using assms(1) by (rule disjI2)
qed
lemma ej_26: joslopjim4
assumes "q"
shows "p ∨ q"
proof (rule disjI2)
show "q" using assms by this
qed
text {* ---------------------------------------------------------------
Ejercicio 27. Demostrar
p ∨ q ⊢ q ∨ p
------------------------------------------------------------------ *}
lemma ejercicio_27: carmarria
assumes "p ∨ q"
shows "q ∨ p"
proof -
have "p | q" using assms(1) by this
moreover
{assume p
have "q | p" using `p` by (rule disjI2)
}
moreover
{assume q
have "q | p" using `q` by (rule disjI1)
}
ultimately show "q | p" by (rule disjE)
qed
lemma ej_27: joslopjim4
assumes "p ∨ q"
shows "q ∨ p"
using assms
proof
assume "p"
then show "q∨p" by(rule disjI2)
next
assume "q"
show "q∨p" using `q` by(rule disjI1)
qed
text {* ---------------------------------------------------------------
Ejercicio 28. Demostrar
q ⟶ r ⊢ p ∨ q ⟶ p ∨ r
------------------------------------------------------------------ *}
lemma ejercicio_28: carmarria
assumes "q ⟶ r"
shows "p ∨ q ⟶ p ∨ r"
proof -
{assume "p | q"
moreover
{assume p
have "p | r" using `p` by (rule disjI1)
}
moreover
{assume q
have r using assms(1) `q` by (rule mp)
have "p | r" using `r` by (rule disjI2)
}
ultimately have "p | r" by (rule disjE)
}
thus "p | q ⟶ p | r" by (rule impI)
qed
lemma ej_28: joslopjim4
assumes "q ⟶ r"
shows "p ∨ q ⟶ p ∨ r"
proof (rule impI)
assume "p∨q"
show "p∨r"
using `p∨q`
proof
assume "p"
show "p∨r" using `p` by (rule disjI1)
next
assume "q"
have "r" using assms `q` by (rule mp)
show "p∨r" using `r` by (rule disjI2)
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 29. Demostrar
p ∨ p ⊢ p
------------------------------------------------------------------ *}
lemma ejercicio_29: carmarria
assumes "p ∨ p"
shows "p"
proof -
have "p | p" using assms(1) by this
moreover
{assume p
}
moreover
{assume p
}
ultimately show p by (rule disjE)
qed
lemma ej_29: joslopjim4
assumes "p ∨ p"
shows "p"
proof (rule ccontr)
assume "¬p"
show False
using assms
proof
assume "p"
show False using `¬p` `p` by (rule notE)
next
assume "p"
show False using `¬p` `p` by (rule notE)
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 30. Demostrar
p ⊢ p ∨ p
------------------------------------------------------------------ *}
lemma ejercicio_30: carmarria
assumes "p"
shows "p ∨ p"
proof -
show "p | p" using assms(1) by (rule disjI1)
qed
lemma ej_30: joslopjim4
assumes "p"
shows "p ∨ p"
proof (rule disjI1)
show "p" using assms by this
qed
text {* ---------------------------------------------------------------
Ejercicio 31. Demostrar
p ∨ (q ∨ r) ⊢ (p ∨ q) ∨ r
------------------------------------------------------------------ *}
lemma ejercicio_31: carmarria
assumes 1: "p ∨ (q ∨ r)"
shows "(p ∨ q) ∨ r"
proof -
have "p | (q | r)" using 1 by this
moreover {assume 2: p
have 3: "p | q" using 2 by (rule disjI1)
have 4: "(p | q) | r" using 3 by (rule disjI1)
}
moreover {assume 5: "q | r"
moreover {assume 6: q
have 7: "p | q" using 6 by (rule disjI2)
have 8: "(p | q) | r " using 7 by (rule disjI1)
}
moreover {assume 9: r
have 10: "(p | q) | r " using 9 by (rule disjI2)
}
ultimately have 11: "(p | q) | r " by (rule disjE)
}
ultimately show "(p | q) | r " by (rule disjE)
qed
lemma ej_31: joslopjim4
assumes "p ∨ (q ∨ r)"
shows "(p ∨ q) ∨ r"
using assms
proof
assume "p"
have "p∨q" using `p` by (rule disjI1)
thus "(p ∨ q) ∨ r" by (rule disjI1)
next
assume "q∨r"
show "(p ∨ q) ∨ r"
using `q∨r`
proof
assume "q"
have "p∨q" using `q` by (rule disjI2)
show "(p ∨ q) ∨ r" using `p∨q` by (rule disjI1)
next
assume "r"
show "(p ∨ q) ∨ r" using `r` by (rule disjI2)
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 32. Demostrar
(p ∨ q) ∨ r ⊢ p ∨ (q ∨ r)
------------------------------------------------------------------ *}
lemma ejercicio_32: carmarria
assumes 1: "(p ∨ q) ∨ r"
shows "p ∨ (q ∨ r)"
proof -
have "(p | q) | r" using 1 by this
moreover {assume 2: "p | q"
moreover {assume 3: p
have 4: "p | (q | r)" using 3 by (rule disjI1)
}
moreover {assume 5: q
have 6: "q | r" using 5 by (rule disjI1)
have 7: "p | (q | r)" using 6 by (rule disjI2)
}
ultimately have 8: " p | (q | r)" by (rule disjE)
}
moreover {assume 9: r
have 10: "q | r" using 9 by (rule disjI2)
have 11: "p | (q | r)" using 10 by (rule disjI2)
}
ultimately show "p | (q | r)" by (rule disjE)
qed
lemma ej_32: joslopjim4
assumes "(p ∨ q) ∨ r"
shows "p ∨ (q ∨ r)"
using assms
proof
assume "p∨q"
show "p ∨ (q ∨ r)"
using `p∨q`
proof
assume "p"
show "p ∨ (q ∨ r)" using `p` by (rule disjI1)
next
assume "q"
have "q∨r" using `q` by (rule disjI1)
show "p ∨ (q ∨ r)" using `q∨r` by (rule disjI2)
qed
next
assume "r"
have "q∨r" using `r` by (rule disjI2)
show "p ∨ (q ∨ r)" using `q∨r` by (rule disjI2)
qed
text {* ---------------------------------------------------------------
Ejercicio 33. Demostrar
p ∧ (q ∨ r) ⊢ (p ∧ q) ∨ (p ∧ r)
------------------------------------------------------------------ *}
lemma ejercicio_33: carmarria
assumes 1: "p ∧ (q ∨ r)"
shows "(p ∧ q) ∨ (p ∧ r)"
proof -
have 2: p using 1 by (rule conjunct1)
have 3: "q | r" using 1 by (rule conjunct2)
moreover {assume 4: q
have 5: "p & q" using 2 4 by (rule conjI)
have 6: "(p & q) | (p & r)" using 5 by (rule disjI1)
}
moreover {assume 7: r
have 8: "p & r" using 2 7 by (rule conjI)
have 9: "(p & q) | (p & r)" using 8 by (rule disjI2)
}
ultimately show "(p & q) | (p & r)" by (rule disjE)
qed
lemma ej_33: joslopjim4
assumes "p ∧ (q ∨ r)"
shows "(p ∧ q) ∨ (p ∧ r)"
proof-
have "p" using assms by (rule conjunct1)
have "q∨r" using assms by (rule conjunct2)
show "(p ∧ q) ∨ (p ∧ r)"
using `q∨r`
proof (rule disjE)
assume "q"
have "p∧q" using `p` `q` by (rule conjI)
show "(p ∧ q) ∨ (p ∧ r)" using `p∧q` by (rule disjI1)
next
assume "r"
have "p∧r" using `p` `r` by (rule conjI)
show "(p ∧ q) ∨ (p ∧ r)" using `p∧r` by (rule disjI2)
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 34. Demostrar
(p ∧ q) ∨ (p ∧ r) ⊢ p ∧ (q ∨ r)
------------------------------------------------------------------ *}
lemma ejercicio_34: carmarria
assumes 1: "(p ∧ q) ∨ (p ∧ r)"
shows "p ∧ (q ∨ r)"
proof -
have "(p & q) | (p & r)" using 1 by this
moreover {assume 2: "p & q"
have 3: p using 2 by (rule conjunct1)
have 4: q using 2 by (rule conjunct2)
have 5: "q | r" using 4 by (rule disjI1)
have 6: "p & (q | r)" using 3 5 by (rule conjI)
}
moreover {assume 7: "p & r"
have 8: p using 7 by (rule conjunct1)
have 9: r using 7 by (rule conjunct2)
have 10: "q | r" using 9 by (rule disjI2)
have 11: "p & (q | r)" using 8 10 by (rule conjI)
}
ultimately show "p & (q | r)" by (rule disjE)
qed
lemma ej_34: joslopjim4
assumes "(p ∧ q) ∨ (p ∧ r)"
shows "p ∧ (q ∨ r)"
using assms
proof
assume "p∧q"
have "p" using `p∧q` by (rule conjunct1)
have "q" using `p∧q` by (rule conjunct2)
have "q∨r" using `q` by (rule disjI1)
show "p∧(q∨r)" using `p` `q∨r` by (rule conjI)
next
assume "p∧r"
have "p" using `p∧r` by (rule conjunct1)
have "r" using `p∧r` by (rule conjunct2)
have "q∨r" using `r` by (rule disjI2)
show "p∧(q∨r)" using `p` `q∨r` by (rule conjI)
qed
text {* ---------------------------------------------------------------
Ejercicio 35. Demostrar
p ∨ (q ∧ r) ⊢ (p ∨ q) ∧ (p ∨ r)
------------------------------------------------------------------ *}
lemma ejercicio_35: carmarria
assumes 1: "p ∨ (q ∧ r)"
shows "(p ∨ q) ∧ (p ∨ r)"
proof -
have "p | (q & r)" using 1 by this
moreover {assume 2: p
have 3: " p | q" using 2 by (rule disjI1)
have 4: " p | r" using 2 by (rule disjI1)
have 5: "(p | q) & (p | r)" using 3 4 by (rule conjI)
}
moreover {assume 6: "q & r"
have 7: q using 6 by (rule conjunct1)
have 8: r using 6 by (rule conjunct2)
have 9: "p | q" using 7 by (rule disjI2)
have 10: "p | r" using 8 by (rule disjI2)
have 11: "(p | q) & (p | r)" using 9 10 by (rule conjI)
}
ultimately show "(p | q) & (p | r)" by (rule disjE)
qed
lemma ej_35: joslopjim4
assumes "p ∨ (q ∧ r)"
shows "(p ∨ q) ∧ (p ∨ r)"
using assms
proof (rule disjE)
assume "p"
have "p∨q" using `p` by (rule disjI1)
have "p∨r" using `p` by (rule disjI1)
show "(p ∨ q) ∧ (p ∨ r)" using `p∨q` `p∨r` by (rule conjI)
next
assume "q∧r"
have "q" using `q∧r` by (rule conjunct1)
have "r" using `q∧r` by (rule conjunct2)
have "p∨q" using `q` by (rule disjI2)
have "p∨r" using `r` by (rule disjI2)
show "(p ∨ q) ∧ (p ∨ r)" using `p∨q` `p∨r` by (rule conjI)
qed
text {* ---------------------------------------------------------------
Ejercicio 36. Demostrar
(p ∨ q) ∧ (p ∨ r) ⊢ p ∨ (q ∧ r)
------------------------------------------------------------------ *}
lemma ejercicio_36: carmarria
assumes 1: "(p ∨ q) ∧ (p ∨ r)"
shows "p ∨ (q ∧ r)"
proof -
have 2: "p | q" using 1 by (rule conjunct1)
moreover {assume 3: p
have 4: "p | (q & r)" using 3 by (rule disjI1)
}
moreover {assume 5: q
have 6: "p | r" using 1 by (rule conjunct2)
moreover {assume 7: p
have 8: "p | (q & r)" using 7 by (rule disjI1)
}
moreover {assume 9: r
have 10: "q & r" using 5 9 by (rule conjI)
have 11: "p | (q & r)" using 10 by (rule disjI2)
}
ultimately have 12: "p | (q & r)" by (rule disjE)
}
ultimately show "p | (q & r)" by (rule disjE)
qed
lemma ej_36: joslopjim4
assumes "(p ∨ q) ∧ (p ∨ r)"
shows "p ∨ (q ∧ r)"
proof-
have "p∨q" using assms by (rule conjunct1)
have "p∨r" using assms by (rule conjunct2)
show "p∨(q ∧ r)"
using `p∨r`
proof
assume "p"
show "p∨(q ∧ r)" using `p` by (rule disjI1)
next
assume "r"
show "p∨(q ∧ r)"
using `p∨q`
proof
assume "p"
show "p∨(q ∧ r)" using `p` by (rule disjI1)
next
assume "q"
have "q∧r" using `q` `r` by (rule conjI)
show "p∨(q ∧ r)" using `q∧r` by (rule disjI2)
qed
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 37. Demostrar
(p ⟶ r) ∧ (q ⟶ r) ⊢ p ∨ q ⟶ r
------------------------------------------------------------------ *}
lemma ejercicio_37: carmarria
assumes 1: "(p ⟶ r) ∧ (q ⟶ r)"
shows "p ∨ q ⟶ r"
proof -
have 2: "p ⟶ r" using 1 by (rule conjunct1)
have 3: "q ⟶ r" using 1 by (rule conjunct2)
{assume 4: "p | q"
moreover {assume 5: p
have 6: r using 2 5 by (rule mp)
}
moreover {assume 7: q
have 8: r using 3 7 by (rule mp)
}
ultimately have r by (rule disjE)
}
thus "p | q ⟶ r" by (rule impI)
qed
lemma ej_37: joslopjim4
assumes "(p ⟶ r) ∧ (q ⟶ r)"
shows "p ∨ q ⟶ r"
proof (rule impI)
assume "p∨q"
have "p⟶r" using assms by (rule conjunct1)
have "q⟶r" using assms by (rule conjunct2)
show "r"
using `p∨q`
proof
assume "p"
show "r" using `p⟶r` `p` by (rule mp)
next
assume "q"
show "r" using `q⟶r` `q` by (rule mp)
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 38. Demostrar
p ∨ q ⟶ r ⊢ (p ⟶ r) ∧ (q ⟶ r)
------------------------------------------------------------------ *}
lemma ejercicio_38: carmarria
assumes 1: "p ∨ q ⟶ r"
shows "(p ⟶ r) ∧ (q ⟶ r)"
proof -
{assume 2: p
have 3: "p | q" using 2 by (rule disjI1)
have 4: r using 1 3 by (rule mp)
}
hence 5: "p ⟶ r" by (rule impI)
{assume 6: q
have 7: "p | q" using 6 by (rule disjI2)
have 8: r using 1 7 by (rule mp)
}
hence 9: "q ⟶ r" by (rule impI)
show "(p ⟶ r) & (q ⟶ r)" using 5 9 by (rule conjI)
qed
lemma ej_38: joslopjim4
assumes "p ∨ q ⟶ r"
shows "(p ⟶ r) ∧ (q ⟶ r)"
proof-
have "p⟶r"
proof (rule impI)
assume "p"
have "p∨q" using `p` by (rule disjI1)
show "r" using assms `p∨q` by (rule mp)
qed
have "q⟶r"
proof (rule impI)
assume "q"
have "p∨q" using `q` by (rule disjI2)
show "r" using assms `p∨q` by (rule mp)
qed
show "(p ⟶ r) ∧ (q ⟶ r)" using `p⟶r` `q⟶r` by (rule conjI)
qed
section {* Negaciones *}
text {* ---------------------------------------------------------------
Ejercicio 39. Demostrar
p ⊢ ¬¬p
------------------------------------------------------------------ *}
lemma ejercicio_39: carmarria
assumes "p"
shows "¬¬p"
proof -
show "~~p" using assms(1) by (rule notnotI)
qed
lemma ej_39: joslopjim4
assumes "p"
shows "¬¬p"
proof-
show "¬¬p" using assms by (rule notnotI)
qed
text {* ---------------------------------------------------------------
Ejercicio 40. Demostrar
¬p ⊢ p ⟶ q
------------------------------------------------------------------ *}
lemma ejercicio_40: carmarria
assumes "¬p"
shows "p ⟶ q"
proof -
{assume p
have "~p" using assms(1) by this
have False using `~p` `p` by (rule notE)
have q using `False` by (rule FalseE)
}
thus "p ⟶ q" by (rule impI)
qed
lemma ej_40: joslopjim4
assumes "¬p"
shows "p ⟶ q"
proof (rule impI)
assume "p"
show "q" using assms `p` by (rule notE)
qed
text {* ---------------------------------------------------------------
Ejercicio 41. Demostrar
p ⟶ q ⊢ ¬q ⟶ ¬p
------------------------------------------------------------------ *}
lemma ejercicio_41: carmarria
assumes 1: "p ⟶ q"
shows "¬q ⟶ ¬p"
proof -
{assume 2: "~q"
have 3: "~p" using 1 2 by (rule mt)
}
thus 4: "~q ⟶ ~p" by (rule impI)
qed
lemma ej_41: joslopjim4
assumes "p ⟶ q"
shows "¬q ⟶ ¬p"
proof (rule impI)
assume "¬q"
show "¬p" using assms `¬q` by (rule mt)
qed
text {* ---------------------------------------------------------------
Ejercicio 42. Demostrar
p∨q, ¬q ⊢ p
------------------------------------------------------------------ *}
lemma ejercicio_42: carmarria
assumes 1: "p∨q" and
2: "¬q"
shows "p"
proof -
have " p | q" using 1 by this
moreover {assume 3: p
}
moreover {assume 4: q
have 5: False using 2 4 by (rule notE)
have 6: p using 5 by (rule FalseE)
}
ultimately show p by (rule disjE)
qed
lemma ej_42: joslopjim4
assumes "p∨q"
"¬q"
shows "p"
using assms(1)
proof
assume "p"
show "p" using `p` by this
next
assume "q"
show "p" using assms(2) `q` by (rule notE)
qed
text {* ---------------------------------------------------------------
Ejercicio 43. Demostrar
p ∨ q, ¬p ⊢ q
------------------------------------------------------------------ *}
lemma ejercicio_43: carmarria
assumes 1: "p ∨ q" and
2: "¬p"
shows "q"
proof -
have " p | q" using 1 by this
moreover {assume 3: p
have 4: False using 2 3 by (rule notE)
have 5: q using 4 by (rule FalseE)
}
moreover {assume 6: q
}
ultimately show q by (rule disjE)
qed
lemma ej_43: joslopjim4
assumes "p ∨ q"
"¬p"
shows "q"
using assms(1)
proof
assume "p"
show "q" using assms(2) `p` by (rule notE)
next
assume "q"
show "q" using `q` by this
qed
text {* ---------------------------------------------------------------
Ejercicio 44. Demostrar
p ∨ q ⊢ ¬(¬p ∧ ¬q)
------------------------------------------------------------------ *}
lemma ejercicio_44: carmarria
assumes 1: "p ∨ q"
shows "¬(¬p ∧ ¬q)"
proof -
have "p | q" using 1 by this
moreover {assume 2: p
{assume 3:"~p & ~q"
have 4: "~p" using 3 by (rule conjunct1)
have 5: False using 4 2 by (rule notE)
}
hence 6: "~(~p & ~q)" by (rule notI)
}
moreover {assume 7: q
{assume 8: "~p & ~q"
have 9: "~q" using 8 by (rule conjunct2)
have 10: False using 9 7 by (rule notE)
}
hence 11: "~(~p & ~q)" by (rule notI)
}
ultimately show "~(~p & ~q)" by (rule disjE)
qed
lemma ej_44: joslopjim4
assumes "p∨q"
shows "¬(¬p∧¬q)"
proof (rule notI)
assume "¬p∧¬q"
show False
using assms
proof
assume "p"
have "¬p" using `¬p∧¬q` by (rule conjunct1)
show False using `¬p` `p` by (rule notE)
next
assume "q"
have "¬q" using `¬p∧¬q` by (rule conjunct2)
show False using `¬q` `q` by (rule notE)
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 45. Demostrar
p ∧ q ⊢ ¬(¬p ∨ ¬q)
------------------------------------------------------------------ *}
lemma ejercicio_45: carmarria
assumes 1: "p ∧ q"
shows "¬(¬p ∨ ¬q)"
proof -
{assume 2: "~p | ~q"
moreover {assume 3: "~p"
have 4: p using 1 by (rule conjunct1)
have 5: False using 3 4 by (rule notE)
}
moreover {assume 6: "~q"
have 7: q using 1 by (rule conjunct2)
have 8: False using 6 7 by (rule notE)
}
ultimately have False by (rule disjE)
}
thus "~(~p | ~q)" by (rule notI)
qed
lemma ej_45: joslopjim4
assumes "p∧q"
shows "¬(¬p∨¬q)"
proof (rule notI)
assume "¬p∨¬q"
then show False
proof (rule disjE)
assume "¬p"
have "p" using assms by (rule conjunct1)
show False using `¬p` `p` by (rule notE)
next
assume "¬q"
have "q" using assms by (rule conjunct2)
show False using `¬q` `q` by (rule notE)
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 46. Demostrar
¬(p ∨ q) ⊢ ¬p ∧ ¬q
------------------------------------------------------------------ *}
lemma ejercicio_46: carmarria
assumes 1: "¬(p ∨ q)"
shows "¬p ∧ ¬q"
proof -
{assume 2: p
have 3: "p | q" using 2 by (rule disjI1)
have 4: False using 1 3 by (rule notE)
}
hence 5: "~p" by (rule notI)
{assume 6: q
have 7: "p | q" using 6 by (rule disjI2)
have 8: False using 1 7 by (rule notE)
}
hence 9: "~q" by (rule notI)
show "~p & ~q" using 5 9 by (rule conjI)
qed
lemma ej_46: joslopjim4
assumes "¬(p ∨ q)"
shows "¬p ∧ ¬q"
proof (rule conjI)
show "¬p"
proof (rule ccontr)
assume "¬¬p"
have "p" using `¬¬p` by (rule notnotD)
have "p∨q" using `p` by (rule disjI1)
show False using assms `p∨q` by (rule notE)
qed
show "¬q"
proof (rule ccontr)
assume "¬¬q"
have "q" using `¬¬q` by (rule notnotD)
have "p∨q" using `q` by (rule disjI2)
show False using assms `p∨q` by (rule notE)
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 47. Demostrar
¬p ∧ ¬q ⊢ ¬(p ∨ q)
------------------------------------------------------------------ *}
lemma ejercicio_47: carmarria
assumes 1: "¬p ∧ ¬q"
shows "¬(p ∨ q)"
proof -
{assume 2: "p | q"
moreover {assume 3: p
have 4: "~p" using 1 by (rule conjunct1)
have 5: False using 4 3 by (rule notE)
}
moreover {assume 6: q
have 7: "~q" using 1 by (rule conjunct2)
have 8: False using 7 6 by (rule notE)
}
ultimately have 9: False by (rule disjE)
}
thus "~(p | q)" by (rule notI)
qed
lemma ej_47: joslopjim4
assumes "¬p∧¬q"
shows "¬(p∨q)"
proof (rule notI)
assume "p∨q"
then show False
proof
assume "p"
have "¬p" using assms by (rule conjunct1)
show False using `¬p` `p` by (rule notE)
next
assume "q"
have "¬q" using assms by (rule conjunct2)
show False using `¬q` `q` by (rule notE)
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 48. Demostrar
¬p ∨ ¬q ⊢ ¬(p ∧ q)
------------------------------------------------------------------ *}
lemma ejercicio_48: carmarria
assumes 1: "¬p ∨ ¬q"
shows "¬(p ∧ q)"
proof -
have "~p | ~q" using 1 by this
moreover {assume 2: "~p"
{assume 3: "p & q"
have 4: p using 3 by (rule conjunct1)
have 5: False using 2 4 by (rule notE)
}
hence 6: "~(p & q)" by (rule notI)
}
moreover {assume 7: "~q"
{assume 8: "p & q"
have 9: q using 8 by (rule conjunct2)
have 10: False using 7 9 by (rule notE)
}
hence 11: "~(p & q)" by (rule notI)
}
ultimately show "~(p & q)" by (rule disjE)
qed
lemma ej_48: joslopjim4
assumes "¬p ∨ ¬q"
shows "¬(p ∧ q)"
proof (rule notI)
assume "p∧q"
have "p" using `p∧q` by (rule conjunct1)
have "q" using `p∧q` by (rule conjunct2)
show False
using assms
proof
assume "¬p"
have "p" using `p∧q` by (rule conjunct1)
show False using `¬p` `p` by (rule notE)
next
assume "¬q"
have "q" using `p∧q` by (rule conjunct2)
show False using `¬q` `q` by (rule notE)
qed
qed
text {* ---------------------------------------------------------------
Ejercicio 49. Demostrar
⊢ ¬(p ∧ ¬p)
------------------------------------------------------------------ *}
lemma ejercicio_49: carmarria
"¬(p ∧ ¬p)"
proof -
{assume 1: "p & ~p"
have 2: p using 1 by (rule conjunct1)
have 3: "~p" using 1 by (rule conjunct2)
have 4: False using 3 2 by (rule notE)
}
thus "~(p & ~p)" by (rule notI)
qed
lemma ej_49: joslopjim4
shows "¬(p∧¬p)"
proof
assume "p∧¬p"
have "p" using `p∧¬p` by (rule conjunct1)
have "¬p" using `p∧¬p` by (rule conjunct2)
show False using `¬p` `p` by (rule notE)
qed
text {* ---------------------------------------------------------------
Ejercicio 50. Demostrar
p ∧ ¬p ⊢ q
------------------------------------------------------------------ *}
lemma ejercicio_50: carmarria
assumes 1: "p ∧ ¬p"
shows "q"
proof -
have 2: p using 1 by (rule conjunct1)
have 3: "~p" using 1 by (rule conjunct2)
have 4: False using 3 2 by (rule notE)
show q using 4 by (rule FalseE)
qed
lemma ej_50: joslopjim4
assumes "p∧¬p"
shows "q"
proof-
have "p" using `p∧¬p` by (rule conjunct1)
have "¬p" using `p∧¬p` by (rule conjunct2)
have False using `¬p` `p` by (rule notE)
then show "q" by (rule FalseE)
qed
text {* ---------------------------------------------------------------
Ejercicio 51. Demostrar
¬¬p ⊢ p
------------------------------------------------------------------ *}
lemma ejercicio_51: carmarria joslopjim4
assumes "¬¬p"
shows "p"
proof -
show p using assms by (rule notnotD)
qed
text {* ---------------------------------------------------------------
Ejercicio 52. Demostrar
⊢ p ∨ ¬p
------------------------------------------------------------------ *}
lemma ejercicio_52: carmarria
"p ∨ ¬p"
proof -
{assume 1: "~(p | ~p)"
{assume 2: p
have 3: "p | ~p" using 2 by (rule disjI1)
have 4: False using 1 3 by (rule notE)
}
hence 5: "~p" by (rule notI)
have 6: "p | ~p" using 5 by (rule disjI2)
have 7: False using 1 6 by (rule notE)
}
hence 8: "~~(p | ~p)" by (rule notI)
show "p | ~p" using 8 by (rule notnotD)
qed
text {* ---------------------------------------------------------------
Ejercicio 53. Demostrar
⊢ ((p ⟶ q) ⟶ p) ⟶ p
------------------------------------------------------------------ *}
lemma ej_53: joslopjim4
shows "((p ⟶ q) ⟶ p) ⟶ p"
proof (rule impI)
assume "(p ⟶ q) ⟶ p"
show "p"
proof (rule ccontr)
assume "¬p"
have "¬(p⟶q)" using `(p ⟶ q) ⟶ p` `¬p` by (rule mt)
have "p⟶q"
proof (rule impI)
assume "p"
show "q" using `¬p` `p` by (rule notE)
qed
show False using `¬(p⟶q)` `p⟶q` by (rule notE)
qed
qed
lemma ejercicio_53: carmarria
"((p ⟶ q) ⟶ p) ⟶ p"
proof -
{assume 1: "(p ⟶ q) ⟶ p"
{assume 2:"~p"
have 3: "~(p ⟶q)" using 1 2 by (rule mt)
{assume 4: p
have 5: False using 2 4 by (rule notE)
have 6: q using 5 by (rule FalseE)
}
hence 7: "p ⟶q" by (rule impI)
have 8: False using 3 7 by (rule notE)
}
hence 9: "~~p" by (rule notI)
have 10: p using 9 by (rule notnotD)
}
thus "((p ⟶ q)⟶p)⟶p" by (rule impI)
qed
text {* ---------------------------------------------------------------
Ejercicio 54. Demostrar
¬q ⟶ ¬p ⊢ p ⟶ q
------------------------------------------------------------------ *}
lemma ej_54: joslopjim4
assumes "¬q ⟶ ¬p"
shows "p ⟶ q"
proof (rule impI)
assume "p"
have "¬¬p" using `p` by (rule notnotI)
have "¬¬q" using assms `¬¬p` by (rule mt)
show "q" using `¬¬q` by (rule notnotD)
qed
lemma ejercicio_54: carmarria
assumes 1: "¬q ⟶ ¬p"
shows "p ⟶ q"
proof -
{assume 2: p
have 3: "~~p" using 2 by (rule notnotI)
have 4: "~~q" using 1 3 by (rule mt)
have 5: q using 4 by (rule notnotD)
}
thus "p ⟶q" by (rule impI)
qed
text {* ---------------------------------------------------------------
Ejercicio 55. Demostrar
¬(¬p ∧ ¬q) ⊢ p ∨ q
------------------------------------------------------------------ *}
lemma ejercicio_55: carmarria
assumes 1: "¬(¬p ∧ ¬q)"
shows "p ∨ q"
proof -
{assume 2: "~(p | q)"
{assume 3: "~p"
{assume 4: "~q"
have 5: "~p & ~q" using 3 4 by (rule conjI)
have 6: False using 1 5 by (rule notE)
}
hence 7: "~~q" by (rule notI)
have 8: q using 7 by (rule notnotD)
have 9: "p | q" using 8 by (rule disjI2)
have 10: False using 2 9 by (rule notE)
}
hence 11: "~~p" by (rule notI)
have 12: p using 11 by(rule notnotD)
have 13: "p | q" using 12 by (rule disjI1)
have 14: False using 2 13 by (rule notE)
}
hence 15: "~~(p | q)" by (rule notI)
show "p | q" using 15 by (rule notnotD)
qed
text {* ---------------------------------------------------------------
Ejercicio 56. Demostrar
¬(¬p ∨ ¬q) ⊢ p ∧ q
------------------------------------------------------------------ *}
lemma ejercicio_56: carmarria
assumes 1: "¬(¬p ∨ ¬q)"
shows "p ∧ q"
proof -
{assume 2: "~p"
have 3: "~p | ~q" using 2 by (rule disjI1)
have 4: False using 1 3 by (rule notE)
}
hence 5: "~~p" by (rule notI)
have 6: p using 5 by (rule notnotD)
{assume 7: "~q"
have 8: "~p | ~q" using 7 by (rule disjI2)
have 9: False using 1 8 by (rule notE)
}
hence 10: "~~q" by (rule notI)
have 11: q using 10 by (rule notnotD)
show 12: " p & q" using 6 11 by (rule conjI)
qed
text {* ---------------------------------------------------------------
Ejercicio 57. Demostrar
¬(p ∧ q) ⊢ ¬p ∨ ¬q
------------------------------------------------------------------ *}
lemma ejercicio_57:
assumes "¬(p ∧ q)"
shows "¬p ∨ ¬q"
oops
text {* ---------------------------------------------------------------
Ejercicio 58. Demostrar
⊢ (p ⟶ q) ∨ (q ⟶ p)
------------------------------------------------------------------ *}
lemma ejercicio_58:
"(p ⟶ q) ∨ (q ⟶ p)"
oops
end