document.write( "Question 1022622: Prove that the two arguments below are valid, using
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Algebra.Com's Answer #638272 by Edwin McCravy(20054)\"\" \"About 
You can put this solution on YOUR website!
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document.write( " 1.      B -> (D -> H)\r\n" );
document.write( " 2.      ~(D -> ~B)               //        H\r\n" );
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document.write( " 3.      (B v D) -> H        1, Importation\r\n" );
document.write( " 4.      ~(~D v ~B)          2, Material implication\r\n" );
document.write( " 5.      ~~D & ~~B           3, DeMorgan's law\r\n" );
document.write( " 6.      D & B               4, Double negation\r\n" );
document.write( " 7.      B & D               6, Commutation \r\n" );
document.write( " 8.      B                   7, Simplification\r\n" );
document.write( " 9.      B v D               8, Addition\r\n" );
document.write( "10.      H                   3,9, Modus Ponens\r\n" );
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document.write( "Edwin
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