document.write( "Question 1155652: SOLVE THE PROOF
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Algebra.Com's Answer #778361 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "1.  P v Q   \r\n" );
document.write( "2.  P → (T → S),  \r\n" );
document.write( "3.  P → T,  \r\n" );
document.write( "4.  S ↔ Q          ├  S\r\n" );
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document.write( "               |5.  ~S                  Assumption for Indirect Proof\r\n" );
document.write( "               |6.  (S → Q) & (Q → S)     4,  Material Equivalence\r\n" );
document.write( "               |7.  (Q → S) & (S → Q)     6,  Commutation\r\n" );
document.write( "               |8.  Q → S                 7,  Simplification\r\n" );
document.write( "               |9.  ~Q                  8,5,  Modus Tollens\r\n" );
document.write( "               |10. Q v P                 1,  Commutation\r\n" );
document.write( "               |11. P                  10,9,  Disjunctive Syllogism\r\n" );
document.write( "               |12. T                   3,11, Modus Ponens    \r\n" );
document.write( "               |13. T → S               2,11, Modus Ponens\r\n" );
document.write( "               |14. S                  13,12, Modus Ponens\r\n" );
document.write( "               |15. ~S & S              5,14, Conjunction\r\n" );
document.write( "16. S                                 Lines 5-15 Indirect Proof\r\n" );
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document.write( "Edwin
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