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		<title>Jalonso en 12:03 20 abr 2019</title>
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&lt;a href=&quot;https://www.glc.us.es/~jalonso/LMF2019/index.php?title=Sol_7&amp;amp;diff=577&amp;amp;oldid=566&quot;&gt;Mostrar los cambios&lt;/a&gt;</summary>
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		<title>Mjoseh en 10:52 9 abr 2019</title>
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		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;p&gt;&lt;b&gt;Página nueva&lt;/b&gt;&lt;/p&gt;&lt;div&gt;&amp;lt;source lang = &amp;quot;isabelle&amp;quot;&amp;gt;&lt;br /&gt;
theory R7_sol&lt;br /&gt;
imports Main &lt;br /&gt;
begin&lt;br /&gt;
&lt;br /&gt;
text {*&lt;br /&gt;
  --------------------------------------------------------------------- &lt;br /&gt;
  El objetivo de esta relación es escribir demostraciones usando sólo&lt;br /&gt;
  las reglas básicas de deducción natural de la lógica proposicional y&lt;br /&gt;
  los métodos rule, erule, frule, drule y assumption.&lt;br /&gt;
&lt;br /&gt;
  Las reglas básicas de la deducción natural son las siguientes:&lt;br /&gt;
  · conjI:          ⟦P; Q⟧ ⟹ P ∧ Q&lt;br /&gt;
  · conjunct1:      P ∧ Q ⟹ P&lt;br /&gt;
  · conjunct2:      P ∧ Q ⟹ Q&lt;br /&gt;
  · conjE:          ⟦P ∧ Q; ⟦P; Q⟧ ⟹ R⟧ ⟹ R&lt;br /&gt;
  · notE:           ⟦¬P; P⟧ ⟹ R&lt;br /&gt;
  · notI:           (P ⟹ False) ⟹ ¬P&lt;br /&gt;
  · mp:             ⟦P ⟶ Q; P⟧ ⟹ Q &lt;br /&gt;
  · mt:             ⟦F ⟶ G; ¬G⟧ ⟹ ¬F &lt;br /&gt;
  · impI:           (P ⟹ Q) ⟹ P ⟶ Q&lt;br /&gt;
  · impE:           ⟦P ⟶ Q; P; Q ⟹ R⟧ ⟹ R&lt;br /&gt;
  · disjI1:         P ⟹ P ∨ Q&lt;br /&gt;
  · disjI2:         Q ⟹ P ∨ Q&lt;br /&gt;
  · disjE:          ⟦P ∨ Q; P ⟹ R; Q ⟹ R⟧ ⟹ R &lt;br /&gt;
  · FalseE:         False ⟹ P&lt;br /&gt;
  · iffI:           ⟦P ⟹ Q; Q ⟹ P⟧ ⟹ P = Q&lt;br /&gt;
  · iffD1:          ⟦Q = P; Q⟧ ⟹ P &lt;br /&gt;
  · iffD2:          ⟦P = Q; Q⟧ ⟹ P&lt;br /&gt;
  · iffE:           ⟦P = Q; ⟦P ⟶ Q; Q ⟶ P⟧ ⟹ R⟧ ⟹ R&lt;br /&gt;
  · notnotD:        ¬¬ P ⟹ P&lt;br /&gt;
  · not_not:        P = ¬¬P&lt;br /&gt;
  · ccontr:         (¬P ⟹ False) ⟹ P&lt;br /&gt;
  · excluded_midle: ¬P ∨ P&lt;br /&gt;
  · classical:      (¬ P ⟹ P) ⟹ P&lt;br /&gt;
  · contrapos_nn    ⟦¬Q; P ⟹ Q⟧ ⟹ ¬P&lt;br /&gt;
  --------------------------------------------------------------------- &lt;br /&gt;
*}&lt;br /&gt;
&lt;br /&gt;
section {* Implicaciones *}&lt;br /&gt;
&lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 1. Demostrar&lt;br /&gt;
       p ⟶ q, p ⊢ q&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej1: &amp;quot;⟦p ⟶ q; p⟧ ⟹ q&amp;quot; &lt;br /&gt;
  apply (erule mp)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  done&lt;br /&gt;
&lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 2. Demostrar&lt;br /&gt;
     p ⟶ q, q ⟶ r, p ⊢ r&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej2: &amp;quot;⟦p ⟶ q; q ⟶ r; p⟧ ⟹ r&amp;quot;&lt;br /&gt;
  apply (erule mp)+&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done  &lt;br /&gt;
&lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 3. Demostrar&lt;br /&gt;
     p ⟶ (q ⟶ r), p ⟶ q, p ⊢ r&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej3a: &amp;quot;⟦p ⟶ (q ⟶ r); p ⟶ q; p⟧ ⟹ r&amp;quot;&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
   apply assumption+&lt;br /&gt;
  done&lt;br /&gt;
&lt;br /&gt;
lemma ej3b: &amp;quot;⟦p ⟶ (q ⟶ r); p ⟶ q; p⟧ ⟹ r&amp;quot;&lt;br /&gt;
  apply (erule impE, assumption+)+&lt;br /&gt;
  done&lt;br /&gt;
&lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 4. Demostrar&lt;br /&gt;
     p ⟶ q, q ⟶ r ⊢ p ⟶ r&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
-- &amp;quot;La demostración detallada es&amp;quot;&lt;br /&gt;
lemma ej4: &amp;quot;⟦p ⟶ q; q ⟶ r⟧ ⟹ p ⟶ r&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule mp)&lt;br /&gt;
  apply (erule mp)&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
&lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 5. Demostrar&lt;br /&gt;
     p ⟶ (q ⟶ r) ⊢ q ⟶ (p ⟶ r)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej5: &amp;quot;p ⟶ (q ⟶ r) ⟹ q ⟶ (p ⟶ r)&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule impE, assumption)&lt;br /&gt;
  apply (erule impE, assumption+)&lt;br /&gt;
  done  &lt;br /&gt;
  &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 6. Demostrar&lt;br /&gt;
     p ⟶ (q ⟶ r) ⊢ (p ⟶ q) ⟶ (p ⟶ r)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej6: &amp;quot;p ⟶ (q ⟶ r) ⟹ (p ⟶ q) ⟶ (p ⟶ r)&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule impE, assumption)&lt;br /&gt;
  apply (erule impE, assumption)&lt;br /&gt;
  apply (erule impE, assumption+)&lt;br /&gt;
  done&lt;br /&gt;
&lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 7. Demostrar&lt;br /&gt;
     p ⊢ q ⟶ p&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej7: &amp;quot;p ⟹ q ⟶ p&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 8. Demostrar&lt;br /&gt;
     ⊢ p ⟶ (q ⟶ p)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej8: &amp;quot;p ⟶ (q ⟶ p)&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
&lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 9. Demostrar&lt;br /&gt;
     p ⟶ q ⊢ (q ⟶ r) ⟶ (p ⟶ r)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej9: &amp;quot;p ⟶ q ⟹ (q ⟶ r) ⟶ (p ⟶ r)&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule impE, assumption)&lt;br /&gt;
  apply (erule impE, assumption+)&lt;br /&gt;
  done&lt;br /&gt;
&lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 10. Demostrar&lt;br /&gt;
     p ⟶ (q ⟶ (r ⟶ s)) ⊢ r ⟶ (q ⟶ (p ⟶ s))&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej10: &amp;quot;p ⟶ (q ⟶ (r ⟶ s)) ⟹ r ⟶ (q ⟶ (p ⟶ s))&amp;quot;&lt;br /&gt;
  apply (rule impI)+&lt;br /&gt;
  apply (erule impE, assumption+)+&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 11. Demostrar&lt;br /&gt;
     ⊢ (p ⟶ (q ⟶ r)) ⟶ ((p ⟶ q) ⟶ (p ⟶ r))&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej11: &amp;quot;(p ⟶ (q ⟶ r)) ⟶ ((p ⟶ q) ⟶ (p ⟶ r))&amp;quot;&lt;br /&gt;
  apply (rule impI)+&lt;br /&gt;
  apply (erule impE, assumption+)+&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 12. Demostrar&lt;br /&gt;
     (p ⟶ q) ⟶ r ⊢ p ⟶ (q ⟶ r)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej12: &amp;quot;(p ⟶ q) ⟶ r ⟹ p ⟶ (q ⟶ r)&amp;quot;&lt;br /&gt;
  apply (rule impI)+&lt;br /&gt;
  apply (rule_tac P=&amp;quot;p ⟶ q&amp;quot; in mp)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
  &lt;br /&gt;
section {* Conjunciones *}&lt;br /&gt;
&lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 13. Demostrar&lt;br /&gt;
     p, q ⊢  p ∧ q&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej13: &amp;quot;⟦p; q⟧ ⟹ p ∧ q&amp;quot;&lt;br /&gt;
  apply (rule conjI)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 14. Demostrar&lt;br /&gt;
     p ∧ q ⊢ p&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej14: &amp;quot;p ∧ q ⟹ p&amp;quot;&lt;br /&gt;
  apply (erule conjunct1)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 15. Demostrar&lt;br /&gt;
     p ∧ q ⊢ q&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej15: &amp;quot;p ∧ q ⟹ q&amp;quot;&lt;br /&gt;
  apply (erule conjunct2)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 16. Demostrar&lt;br /&gt;
     p ∧ (q ∧ r) ⊢ (p ∧ q) ∧ r&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej16: &amp;quot;p ∧ (q ∧ r) ⟹ (p ∧ q) ∧ r&amp;quot;&lt;br /&gt;
  apply (rule conjI)&lt;br /&gt;
   apply (rule conjI)&lt;br /&gt;
    apply (erule conjunct1)&lt;br /&gt;
   apply (drule conjunct2)&lt;br /&gt;
   apply (erule conjunct1)&lt;br /&gt;
  apply (drule conjunct2)&lt;br /&gt;
  apply (erule conjunct2)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 17. Demostrar&lt;br /&gt;
     (p ∧ q) ∧ r ⊢ p ∧ (q ∧ r)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej17: &amp;quot;(p ∧ q) ∧ r ⟹ p ∧ (q ∧ r)&amp;quot;&lt;br /&gt;
  apply (rule conjI)&lt;br /&gt;
   apply (drule conjunct1)&lt;br /&gt;
   apply (erule conjunct1)&lt;br /&gt;
  apply (rule conjI)&lt;br /&gt;
   apply (drule conjunct1)&lt;br /&gt;
   apply (erule conjunct2)&lt;br /&gt;
  apply (erule conjunct2)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 18. Demostrar&lt;br /&gt;
     p ∧ q ⊢ p ⟶ q&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej18: &amp;quot;p ∧ q ⟹ p ⟶ q&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule conjunct2)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 19. Demostrar&lt;br /&gt;
     (p ⟶ q) ∧ (p ⟶ r) ⊢ p ⟶ q ∧ r   &lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej19: &amp;quot;(p ⟶ q) ∧ (p ⟶ r) ⟹ p ⟶ q ∧ r&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (rule conjI)&lt;br /&gt;
   apply (drule conjunct1)&lt;br /&gt;
   apply (erule impE)&lt;br /&gt;
    apply assumption&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (drule conjunct2)&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 20. Demostrar&lt;br /&gt;
     p ⟶ q ∧ r ⊢ (p ⟶ q) ∧ (p ⟶ r)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej20: &amp;quot;p ⟶ q ∧ r ⟹ (p ⟶ q) ∧ (p ⟶ r)&amp;quot;&lt;br /&gt;
  apply (rule conjI)&lt;br /&gt;
   apply (rule impI)&lt;br /&gt;
   apply (erule impE)&lt;br /&gt;
    apply assumption&lt;br /&gt;
    apply (erule conjunct1)&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (erule conjunct2)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 21. Demostrar&lt;br /&gt;
     p ⟶ (q ⟶ r) ⊢ p ∧ q ⟶ r&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej21_1: &amp;quot;p ⟶ (q ⟶ r) ⟹ p ∧ q ⟶ r&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule conjE)&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 22. Demostrar&lt;br /&gt;
     p ∧ q ⟶ r ⊢ p ⟶ (q ⟶ r)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej22: &amp;quot;p ∧ q ⟶ r ⟹ p ⟶ (q ⟶ r)&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
    apply (rule conjI)&lt;br /&gt;
    apply assumption+&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 23. Demostrar&lt;br /&gt;
     (p ⟶ q) ⟶ r ⊢ p ∧ q ⟶ r&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej23: &amp;quot;(p ⟶ q) ⟶ r ⟹ p ∧ q ⟶ r&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
   apply (rule impI)&lt;br /&gt;
   apply (erule conjunct2)&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 24. Demostrar&lt;br /&gt;
     p ∧ (q ⟶ r) ⊢ (p ⟶ q) ⟶ r&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej24: &amp;quot;p ∧ (q ⟶ r) ⟹ (p ⟶ q) ⟶ r&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule conjE)&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
   apply assumption+&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
section {* Disyunciones *}&lt;br /&gt;
&lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 25. Demostrar&lt;br /&gt;
     p ⊢ p ∨ q&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej25: &amp;quot;p ⟹ p ∨ q&amp;quot;&lt;br /&gt;
  apply (erule disjI1)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 26. Demostrar&lt;br /&gt;
     q ⊢ p ∨ q&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej26: &amp;quot;q ⟹ p ∨ q&amp;quot;&lt;br /&gt;
  apply (erule disjI2)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 27. Demostrar&lt;br /&gt;
     p ∨ q ⊢ q ∨ p&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej27: &amp;quot;p ∨ q ⟹ q ∨ p&amp;quot;&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule disjI2)&lt;br /&gt;
  apply (erule disjI1)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 28. Demostrar&lt;br /&gt;
     q ⟶ r ⊢ p ∨ q ⟶ p ∨ r&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej28: &amp;quot;q ⟶ r ⟹ p ∨ q ⟶ p ∨ r&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule disjI1)&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (erule disjI2)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 29. Demostrar&lt;br /&gt;
     p ∨ p ⊢ p&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej29: &amp;quot;p ∨ p ⟹ p&amp;quot;&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply assumption+&lt;br /&gt;
  done&lt;br /&gt;
&lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 30. Demostrar&lt;br /&gt;
     p ⊢ p ∨ p&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej30: &amp;quot;p ⟹ p ∨ p&amp;quot;&lt;br /&gt;
  apply (erule disjI1)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 31. Demostrar&lt;br /&gt;
     p ∨ (q ∨ r) ⊢ (p ∨ q) ∨ r&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej31: &amp;quot;p ∨ (q ∨ r) ⟹ (p ∨ q) ∨ r&amp;quot;&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (rule disjI1)&lt;br /&gt;
   apply (erule disjI1)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (rule disjI1)&lt;br /&gt;
   apply (erule disjI2)&lt;br /&gt;
  apply (erule disjI2)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 32. Demostrar&lt;br /&gt;
     (p ∨ q) ∨ r ⊢ p ∨ (q ∨ r)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej32: &amp;quot;(p ∨ q) ∨ r ⟹ p ∨ (q ∨ r)&amp;quot;&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule disjE)&lt;br /&gt;
    apply (erule disjI1)&lt;br /&gt;
   apply (rule disjI2)&lt;br /&gt;
   apply (erule disjI1)&lt;br /&gt;
  apply (rule disjI2)&lt;br /&gt;
  apply (erule disjI2)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 33. Demostrar&lt;br /&gt;
     p ∧ (q ∨ r) ⊢ (p ∧ q) ∨ (p ∧ r)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej33: &amp;quot;p ∧ (q ∨ r) ⟹ (p ∧ q) ∨ (p ∧ r)&amp;quot;&lt;br /&gt;
  apply (erule conjE)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (rule disjI1)&lt;br /&gt;
   apply (rule conjI)&lt;br /&gt;
    apply assumption&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (rule disjI2)&lt;br /&gt;
  apply (rule conjI)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 34. Demostrar&lt;br /&gt;
     (p ∧ q) ∨ (p ∧ r) ⊢ p ∧ (q ∨ r)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej34: &amp;quot;(p ∧ q) ∨ (p ∧ r) ⟹ p ∧ (q ∨ r)&amp;quot;&lt;br /&gt;
  apply (rule conjI)&lt;br /&gt;
   apply (erule disjE)&lt;br /&gt;
    apply (erule conjunct1)&lt;br /&gt;
   apply (erule conjunct1)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule conjE)&lt;br /&gt;
   apply (rule disjI1)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (erule conjE)&lt;br /&gt;
  apply (erule disjI2)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 35. Demostrar&lt;br /&gt;
     p ∨ (q ∧ r) ⊢ (p ∨ q) ∧ (p ∨ r)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej35: &amp;quot;p ∨ (q ∧ r) ⟹ (p ∨ q) ∧ (p ∨ r)&amp;quot;&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (rule conjI)&lt;br /&gt;
    apply (erule disjI1)&lt;br /&gt;
   apply (erule disjI1)&lt;br /&gt;
  apply (erule conjE)&lt;br /&gt;
  apply (rule conjI)&lt;br /&gt;
   apply (erule disjI2)&lt;br /&gt;
  apply (erule disjI2)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 36. Demostrar&lt;br /&gt;
     (p ∨ q) ∧ (p ∨ r) ⊢ p ∨ (q ∧ r)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej36: &amp;quot;(p ∨ q) ∧ (p ∨ r) ⟹ p ∨ (q ∧ r)&amp;quot;&lt;br /&gt;
  apply (erule conjE)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule disjI1)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule disjI1)&lt;br /&gt;
  apply (rule disjI2)&lt;br /&gt;
  apply (rule conjI)&lt;br /&gt;
   apply assumption+&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 37. Demostrar&lt;br /&gt;
     (p ⟶ r) ∧ (q ⟶ r) ⊢ p ∨ q ⟶ r&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej37: &amp;quot;(p ⟶ r) ∧ (q ⟶ r) ⟹ p ∨ q ⟶ r&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule conjE)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule impE, assumption+)+&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 38. Demostrar&lt;br /&gt;
     p ∨ q ⟶ r ⊢ (p ⟶ r) ∧ (q ⟶ r)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej38: &amp;quot;p ∨ q ⟶ r ⟹ (p ⟶ r) ∧ (q ⟶ r)&amp;quot;&lt;br /&gt;
  apply (rule conjI)&lt;br /&gt;
   apply (rule impI)&lt;br /&gt;
   apply (erule impE)&lt;br /&gt;
    apply (erule disjI1)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
  apply (erule disjI2)&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
section {* Negación *}&lt;br /&gt;
&lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 39. Demostrar&lt;br /&gt;
     p ⊢ ¬¬p&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej39: &amp;quot;p ⟹ ¬¬p&amp;quot;&lt;br /&gt;
  apply (rule notI)&lt;br /&gt;
  apply (erule notE)&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 40. Demostrar&lt;br /&gt;
     ¬p ⊢ p ⟶ q&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej40: &amp;quot;¬p ⟹ p ⟶ q&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule notE)&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 41. Demostrar&lt;br /&gt;
     p ⟶ q ⊢ ¬q ⟶ ¬p&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej41: &amp;quot;p ⟶ q ⟹ ¬q ⟶ ¬p&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (rule notI)&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (erule notE)&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 42. Demostrar&lt;br /&gt;
     p ∨ q, ¬q ⊢ p&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej42: &amp;quot;⟦p ∨ q; ¬q⟧ ⟹ p&amp;quot;&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (erule notE)&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 43. Demostrar&lt;br /&gt;
     p ∨ q, ¬p ⊢ q&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej43: &amp;quot;⟦p ∨ q; ¬p⟧ ⟹ q&amp;quot;&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule notE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 44. Demostrar&lt;br /&gt;
     p ∨ q ⊢ ¬(¬p ∧ ¬q)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej44: &amp;quot;p ∨ q ⟹ ¬(¬p ∧ ¬q)&amp;quot;&lt;br /&gt;
  apply (rule notI)&lt;br /&gt;
  apply (erule conjE)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule notE, assumption)+&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 45. Demostrar&lt;br /&gt;
     p ∧ q ⊢ ¬(¬p ∨ ¬q)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej45: &amp;quot;p ∧ q ⟹ ¬(¬p ∨ ¬q)&amp;quot;&lt;br /&gt;
  apply (rule notI)&lt;br /&gt;
  apply (erule conjE)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule notE, assumption)+&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 46. Demostrar&lt;br /&gt;
     ¬(p ∨ q) ⊢ ¬p ∧ ¬q&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej46: &amp;quot;¬(p ∨ q) ⟹ ¬p ∧ ¬q&amp;quot;&lt;br /&gt;
  apply (rule conjI)&lt;br /&gt;
   apply (rule notI)&lt;br /&gt;
   apply (erule notE)&lt;br /&gt;
   apply (erule disjI1)&lt;br /&gt;
  apply (rule notI)&lt;br /&gt;
  apply (erule notE)&lt;br /&gt;
  apply (erule disjI2)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 47. Demostrar&lt;br /&gt;
     ¬p ∧ ¬q ⊢ ¬(p ∨ q)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej47: &amp;quot;¬p ∧ ¬q ⟹ ¬(p ∨ q)&amp;quot;&lt;br /&gt;
  apply (rule notI)&lt;br /&gt;
  apply (erule conjE)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule notE, assumption)+&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 48. Demostrar&lt;br /&gt;
     ¬p ∨ ¬q ⊢ ¬(p ∧ q)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej48: &amp;quot;¬p ∨ ¬q ⟹ ¬(p ∧ q)&amp;quot;&lt;br /&gt;
  apply (rule notI)&lt;br /&gt;
  apply (erule conjE)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule notE, assumption)+&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 49. Demostrar&lt;br /&gt;
     ⊢ ¬(p ∧ ¬p)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej49: &amp;quot;¬(p ∧ ¬p)&amp;quot;&lt;br /&gt;
  apply (rule notI)&lt;br /&gt;
  apply (erule conjE)&lt;br /&gt;
  apply (erule notE)&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 50. Demostrar&lt;br /&gt;
     p ∧ ¬p ⊢ q&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej50: &amp;quot;p ∧ ¬p ⟹ q&amp;quot;&lt;br /&gt;
  apply (erule conjE)&lt;br /&gt;
  apply (erule notE)&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 51. Demostrar&lt;br /&gt;
     ¬¬p ⊢ p&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej51: &amp;quot;¬¬p ⟹ p&amp;quot;&lt;br /&gt;
  apply (erule notnotD)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 52. Demostrar&lt;br /&gt;
     ⊢ p ∨ ¬p&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej52: &amp;quot;p ∨ ¬p&amp;quot;&lt;br /&gt;
  apply (cut_tac P=&amp;quot;¬p&amp;quot; in excluded_middle)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
  apply (rule disjI1)&lt;br /&gt;
   apply (erule notnotD)&lt;br /&gt;
  apply (erule disjI2)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 53. Demostrar&lt;br /&gt;
     ⊢ ((p ⟶ q) ⟶ p) ⟶ p&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej53: &amp;quot;((p ⟶ q) ⟶ p) ⟶ p&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (rule ccontr)&lt;br /&gt;
  apply (cut_tac P=&amp;quot;p ⟶ q&amp;quot; in excluded_middle)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule_tac P=&amp;quot;p ⟶ q&amp;quot; in notE)&lt;br /&gt;
   apply (rule impI)&lt;br /&gt;
   apply (erule notE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (erule notE)&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 54. Demostrar&lt;br /&gt;
     ¬q ⟶ ¬p ⊢ p ⟶ q&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej54: &amp;quot;¬q ⟶ ¬p ⟹ p ⟶ q&amp;quot;&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (rule ccontr)&lt;br /&gt;
  apply (erule impE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (erule notE)+&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 55. Demostrar&lt;br /&gt;
     ¬(¬p ∧ ¬q) ⊢ p ∨ q&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej55: &amp;quot;¬(¬p ∧ ¬q) ⟹ p ∨ q&amp;quot;&lt;br /&gt;
  apply (cut_tac P=p in excluded_middle)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
    apply (cut_tac P=q in excluded_middle)&lt;br /&gt;
   apply (erule disjE)&lt;br /&gt;
    apply (erule notE)&lt;br /&gt;
    apply (rule conjI)&lt;br /&gt;
     apply assumption+&lt;br /&gt;
   apply (erule disjI2)&lt;br /&gt;
  apply (erule disjI1)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 56. Demostrar&lt;br /&gt;
     ¬(¬p ∨ ¬q) ⊢ p ∧ q&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej56: &amp;quot;¬(¬p ∨ ¬q) ⟹ p ∧ q&amp;quot;&lt;br /&gt;
  apply (rule conjI)&lt;br /&gt;
   apply (rule ccontr)&lt;br /&gt;
   apply (erule notE)&lt;br /&gt;
   apply (erule disjI1)&lt;br /&gt;
  apply (rule ccontr)&lt;br /&gt;
  apply (erule notE)&lt;br /&gt;
  apply (erule disjI2)&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 57. Demostrar&lt;br /&gt;
     ¬(p ∧ q) ⊢ ¬p ∨ ¬q&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej57: &amp;quot;¬(p ∧ q) ⟹ ¬p ∨ ¬q&amp;quot;&lt;br /&gt;
  apply (cut_tac P=p in excluded_middle)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule disjI1)&lt;br /&gt;
  apply (cut_tac P=q in excluded_middle)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (erule disjI2)&lt;br /&gt;
  apply (erule notE)&lt;br /&gt;
  apply (rule conjI)&lt;br /&gt;
   apply assumption+&lt;br /&gt;
  done&lt;br /&gt;
    &lt;br /&gt;
text {* --------------------------------------------------------------- &lt;br /&gt;
  Ejercicio 58. Demostrar&lt;br /&gt;
     ⊢ (p ⟶ q) ∨ (q ⟶ p)&lt;br /&gt;
  ------------------------------------------------------------------ *}&lt;br /&gt;
&lt;br /&gt;
lemma ej58: &amp;quot;(p ⟶ q) ∨ (q ⟶ p)&amp;quot;&lt;br /&gt;
  apply (cut_tac P=p in excluded_middle)&lt;br /&gt;
  apply (erule disjE)&lt;br /&gt;
   apply (rule disjI1)&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply (erule notE)&lt;br /&gt;
   apply assumption&lt;br /&gt;
  apply (rule disjI2)&lt;br /&gt;
  apply (rule impI)&lt;br /&gt;
  apply assumption&lt;br /&gt;
  done&lt;br /&gt;
&lt;br /&gt;
end&lt;br /&gt;
&lt;br /&gt;
&amp;lt;/source&amp;gt;&lt;/div&gt;</summary>
		<author><name>Mjoseh</name></author>
		
	</entry>
</feed>