document.write( "Question 1086495: p->negation q , q disjunction r , negation s , negation r is a valid inference
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Algebra.Com's Answer #701361 by Edwin McCravy(20054)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "1.  p->~q\r\n" );
document.write( "2.  qvr\r\n" );
document.write( "3.  ~s        /~r\r\n" );
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document.write( "It is not valid because: \r\n" );
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document.write( "p->~q / qvr / ~s // ~r\r\n" );
document.write( "F->FT   TvT   FT    FT   <--a case where the premises are \r\n" );
document.write( "                            all true and the conclusion false \r\n" );
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document.write( "Edwin
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