document.write( "Question 1009334: Derive: A v ~B
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Algebra.Com's Answer #624873 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Proof by contradiction\r
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NumberStatementLines UsedReason
1(F v G) v (A v ~B)
2F -> A
3B -> ~G
.:A v ~B
5~(A v ~B)AIP
6~A & ~~B5DM
7~A & B6DN
8B & ~A7Comm
9~A7Simp
10B8Simp
11~F2,9MT
12~G3,10MP
13~F & ~G11,12Conj
14~(F v G)13DM
15A v ~B1,14DS
16~B15,9DS
17B & ~B10,16Conj
18A v ~B5-17IP
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\n" ); document.write( "\n" ); document.write( "Acroynyms/Abbreviations used\r
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\n" ); document.write( "\n" ); document.write( "AIP = assumption for indirect proof
\n" ); document.write( "Comm = commutation
\n" ); document.write( "Conj = conjunction
\n" ); document.write( "IP = indirect proof
\n" ); document.write( "DM = de morgan's law
\n" ); document.write( "DN = double negation
\n" ); document.write( "DS = disjunctive syllogism
\n" ); document.write( "MP = modus ponens
\n" ); document.write( "MT = modus tollens
\n" ); document.write( "Simp = simplification
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