Question 483036
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The truth of *[tex \Large S\ \small{\vee}\Large\ Q] tells you nothing about the truth of *[tex \Large \neg{P}\ \rightarrow\ \neg{S}].  In the first place, S could be either true or false provided Q was true.  If S is false AND *[tex \Large \neg{P}\ \rightarrow\ \neg{S}] (which is what we were trying to prove) is true, then certainly P -- but so what?  That tells you nothing about not S.  Then again, S could just as easily be true which tells you nothing about P.


So either the answer is "Cannot be proven" or you left off a "Given" or two.


John
*[tex \LARGE e^{i\pi} + 1 = 0]
My calculator said it, I believe it, that settles it
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