document.write( "Question 1205405: 1. C ⊃ (D v A) /~C v D\r
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Algebra.Com's Answer #842194 by Edwin McCravy(20063)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Here is a shorter direct proof.  It requires Material Implication\r\n" );
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document.write( "1. C ⊃ (D v A) \r\n" );
document.write( "2. A ⊃ H\r\n" );
document.write( "3. ~H           /~C v D\r\n" );
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document.write( "4. ~C v (D v A)     1, Material Implication\r\n" );
document.write( "5. (~C v D) v A     4, Association\r\n" );
document.write( "6. ~A             2,3, Modus Tollens\r\n" );
document.write( "7. A v (~C v D)     5, Commutation\r\n" );
document.write( "8. ~C v D         7,6, Disjunctive Syllogism\r\n" );
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document.write( "Edwin
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