document.write( "Question 1126615: Prove by direct proof. (use rules of interference)
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Algebra.Com's Answer #742988 by solver91311(24713) $\"\"$ $\"About$

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document.write( "1.   ~A -> (C and D)\r\n" );
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document.write( "2.    A -> B\r\n" );
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document.write( "3.   ~B         |  C\r\n" );
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document.write( "4.   ~A            3,2 Modus Tollens\r\n" );
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document.write( "5.   C and D       4,1 Modus Ponens\r\n" );
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document.write( "6.   Therefore C   5   Simplification								\r\n" );
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\n" ); document.write( "John
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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