SOLUTION: (A&B)->C B&~C/ ~A (indirect proof)

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Question 1131581: (A&B)->C
B&~C/ ~A (indirect proof)
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!

1.  (A&B)->C
2.  B&~C        / ~A (indirect proof)

           | 3.  ~~A        AIP
           | 4.  A       3. DN
           | 5.  B       2, Simp.
           | 6.  ~C&B    2, Commutation
           | 7.  ~C      6, Simp.
           | 8.  A&B     4,5, Conj.
           | 9.  C       1,8, MP
           |10.  C&~C    9,7, Conj.    <--(contradiction)
11. ~A            Lines 3-10  IP

Edwin