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Hi I'm having trouble solving a Fitch Style Proof and I was hoping someone would be able to help me.

Premises: 

A ^ (B v C)
B => D
C => E

Goal:

~E => D
aioobe
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user3727903
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    This question doesn't quite fit the scope of SO. You may get a better responce from the mathematics StackExchange site [here](http://math.stackexchange.com/). – embedded_guy Jun 10 '14 at 22:34

1 Answers1

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(1)   A /\ (B \/ C)  premise
(2)   B -> D         premise
(3)   C -> E         premise
     .--------------------------------------------.
(4)  | ~E            assumption                   |
(5)  | B \/ C        /\ elimination of 1          |
     | .--------------------------------------.   |
(6)  | | B          assumption                |   |
(7)  | | D          -> elimination 2          |   |
     | '--------------------------------------'   |
     | .--------------------------------------.   |
(8)  | | C          assumption                |   |
(9)  | | E          -> elimination 3          |   |
(10) | | cont       contradiction             |   |
(11) | | D          ! elimination 10          |   |
     | '--------------------------------------'   |
(12) |  D           \/ elimination 5, 6-7, 8-11   |
     '--------------------------------------------'
(13) ~E -> D        -> introduction 4-12
aioobe
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