document.write( "Question 1194113: 55.\r
\n" ); document.write( "\n" ); document.write( "1. (L ≡ N) ⊃ C\r
\n" ); document.write( "\n" ); document.write( "2. (L ≡ N) v (P ⊃ ~E)\r
\n" ); document.write( "\n" ); document.write( "3. ~E ⊃ C\r
\n" ); document.write( "\n" ); document.write( "4. ~C /~P\r
\n" ); document.write( "\n" ); document.write( "56.\r
\n" ); document.write( "\n" ); document.write( "1. ~N ⊃ [(B ⊃ D) ⊃ (N v ~E)]\r
\n" ); document.write( "\n" ); document.write( "2. (B ⊃ E) ⊃ ~N\r
\n" ); document.write( "\n" ); document.write( "3. B ⊃ D\r
\n" ); document.write( "\n" ); document.write( "4. D ⊃ E /~D\r
\n" ); document.write( "\n" ); document.write( "5. ~E 1,3, MD\r
\n" ); document.write( "\n" ); document.write( "N v ~ E 2,5 Add\r
\n" ); document.write( "\n" ); document.write( "57.\r
\n" ); document.write( "\n" ); document.write( "1. G ⊃ [~O ⊃ (G ⊃ D)]\r
\n" ); document.write( "\n" ); document.write( "2. O v G\r
\n" ); document.write( "\n" ); document.write( "3. ~O /D
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Algebra.Com's Answer #826292 by math_tutor2020(3817)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "Please only post one problem at a time.\r
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\n" ); document.write( "\n" ); document.write( "I'll do problem 55 to get you started.
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NumberStatementLine(s) UsedReason
1(L = N) -> C
2(L = N) v (P -> ~E)
3~E -> C
4~C
:.~P
5~~E3, 4Modus Tollens
6~(L = N)1, 4Modus Tollens
7P -> ~E2, 6Disjunctive Syllogism
8~P7, 5Modus Tollens

\n" ); document.write( "I used a standard equal sign in place of a triple equal sign. I used arrows in place of the horseshoe symbols.\r
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\n" ); document.write( "\n" ); document.write( "For more information, check out the various rules of inference and rules of replacement as shown in the link below.
\n" ); document.write( "https://logiccurriculum.com/2019/02/09/rules-for-proofs/
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