document.write( "Question 196020: I need help finishing this proof.
\n" ); document.write( "A v (~B v ~C), A -> (D -> E), ~(~B v ~D) :. C -> (D -> E)\r
\n" ); document.write( "\n" ); document.write( "1. A v (~B v ~C)
\n" ); document.write( "2. A -> (D -> E)
\n" ); document.write( "3. ~(~B v ~D) \n" ); document.write( "

Algebra.Com's Answer #147001 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "1.  A v (~B v ~C)\r\n" );
document.write( "2.  A -> (D -> E) \r\n" );
document.write( "3.  ~(~B v ~D)            :. C -> (D -> E) \r\n" );
document.write( "--------------------------\r\n" );
document.write( "4.  A v ~(~~B & ~~C)                    1    De Morgan's Law\r\n" );
document.write( "5.  A v ~(B & C)                        4    Double Negation\r\n" );
document.write( "6.  ~(B & C) v A                        5    Commutation\r\n" );
document.write( "7.  (B & C) -> A                        6    Material Implication\r\n" );
document.write( "8.  B -> (C -> A)                       7    Exportation\r\n" );
document.write( "----\r\n" );
document.write( "9. ~~B & ~~D                            3    De Morgan's Law\r\n" );
document.write( "10. B & D                               9    Double Negation\r\n" );
document.write( "11. B                                  10    Simplification\r\n" );
document.write( "12. C -> A                           8,11    Modus Ponens\r\n" );
document.write( "13. C -> (D -> E)                    12,2    Hypothetical Syllogism\r\n" );
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