document.write( "Question 1061571: ~ w → ~ a
\n" ); document.write( "~ ( w ٨p ) V s
\n" ); document.write( "S →b
\n" ); document.write( "~ (a ٨~ p)
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\n" ); document.write( "a →b \r
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\n" ); document.write( "\n" ); document.write( "Formal proof written form
\n" ); document.write( "Statements and their reasons \n" ); document.write( "
Algebra.Com's Answer #676400 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "I see you posted it again. Apparently your prof doesn't \r\n" );
document.write( "want either an indirect truth table or conditional proof.\r\n" );
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document.write( "OK, here it is, but we must use material implication.\r\n" );
document.write( "Have you studied that? \r\n" );
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document.write( " 1. ~w->~a\r\n" );
document.write( " 2. ~(w٨p)vs\r\n" );
document.write( " 3. s->b\r\n" );
document.write( " 4. ~(a٨~p)  / a->b\r\n" );
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document.write( " 5. ~~a->~~w           1, transposition\r\n" );
document.write( " 6. a->w               5, double negation\r\n" );
document.write( " 7. ~av~~p             4, DeMorgan's law\r\n" );
document.write( " 8. ~avp               7, double negation\r\n" );
document.write( " 9. a->p               8, material implication\r\n" );
document.write( "10. a->(w٨p)           6,9, composition  \r\n" );
document.write( "11. (w٨p)->s           2, material implication\r\n" );
document.write( "12. a->s               10,11, hypothetical syllogism\r\n" );
document.write( "13. a->b               12,3, hypothetical syllogism\r\n" );
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document.write( "Edwin
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