Question 869909
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Given 
1.  P &#8801; ~C
2.  ~(P & D)
3.  D
Prove C
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4.  ~P v ~D                             2         De Morgan's Law
5.  ~D v ~P                             4         Commutation
6.  ~~D                                 3         Double Negation
7.  ~P                                  5,6       Disjunctive Syllogism
8.  (P -> ~C) * (~C -> P)               1         Material Equivalence
9.  (~C -> P) * (P -> ~C)               8         Commutation
10. ~C -> P                             9         Simplification
11. ~C -> ~~P                           10        Double Negation
12. ~~C                                 11,7      Modus Tollens
13. C                                   12        Double Negation
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