Question 1126615
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1.   ~A -> (C and D)

2.    A -> B

3.   ~B         |  C

4.   ~A            3,2 Modus Tollens

5.   C and D       4,1 Modus Ponens

6.   Therefore C   5   Simplification								
								
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John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
<img src="http://c0rk.blogs.com/gr0undzer0/darwin-fish.jpg">
*[tex \Large \ \
*[tex \LARGE \ \ \ \ \ \ \ \ \ \  
								
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