document.write( "Question 677564: Prove this
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\n" ); document.write( "\n" ); document.write( "I don't understand where to go from here, I appreciate the help very much! I need to better understand the concept from this example \n" ); document.write( "
Algebra.Com's Answer #420940 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "1.   P ∨ Q\r\n" );
document.write( "2.   (Q ∙ ~R) → S\r\n" );
document.write( "3.   R → P \r\n" );
document.write( "4.   ~P         ∴ S \r\n" );
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document.write( "5.   ~R                3,4   Modus Tollens\r\n" );
document.write( "6.   Q                 1,4   Disjunctive Syllogism\r\n" );
document.write( "7.   Q ∙ ~R            6,5   Conjunction\r\n" );
document.write( "8.   S                 2,7   Modus Ponens\r\n" );
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