document.write( "Question 193061: Construct Conditional Proofs\r
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\n" ); document.write( "\n" ); document.write( "1. P → Q
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Algebra.Com's Answer #144910 by jim_thompson5910(35256)\"\" \"About 
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document.write( "1. P → Q\r\n" );
document.write( "2. (P • Q) → R\r\n" );
document.write( "3. P → (R → S)\r\n" );
document.write( "4. (R • S) → T / P → T\r\n" );
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document.write( "5.   P                               Assumption\r\n" );
document.write( "6.   Q                        1,5    Modus Ponens\r\n" );
document.write( "7.   P • Q                    5,6    Conjunction \r\n" );
document.write( "8.   R                        2,7    Modus Ponens\r\n" );
document.write( "9.   P • R                    5,8    Conjunction\r\n" );
document.write( "10.  (P • R) -> S               3    Exportation\r\n" );
document.write( "11.  S                       10,9    Modus Ponens\r\n" );
document.write( "12.  R • S                   8,11    Conjunction\r\n" );
document.write( "13.  T                       4,12    Modus Ponens\r\n" );
document.write( "14.  P -> T                  5,13    Conditional Proof\r\n" );
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