document.write( "Question 1028652: Natural Deduction\r
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Algebra.Com's Answer #643777 by Edwin McCravy(20054)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "1. (Av~B)⊃[(A+C)⊃B]\r\n" );
document.write( "2. ~B              /  A⊃~C\r\n" );
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document.write( "3. [(Av~B)•(A&C)]⊃B          1, Importation\r\n" );
document.write( "4. ~[(Av~B)•(A•C)]           3,2 Modus Tollens\r\n" );
document.write( "5. ~(Av~B)v~(A•C)            4, DeMorgan's law\r\n" );
document.write( "6. ~BvA                      2, Addition\r\n" );
document.write( "7. Av~B                      6, Commutation\r\n" );
document.write( "8. ~~(Av~B)                  7, Double negation\r\n" );
document.write( "9. ~(A•C)                    5,8, Disjunctive syllogism\r\n" );
document.write( "10. ~Av~C                    9, DeMorgan's law\r\n" );
document.write( "11. A⊃~C                     10, Material implication\r\n" );
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document.write( "Edwin
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