document.write( "Question 1179972: Use an ordinary proof (not conditional or indirect) to solve the following arguments\r
\n" ); document.write( "\n" ); document.write( "1. O ⊃ (Q • N)
\n" ); document.write( "2. (N Ú E) ⊃ S/ O ⊃ S \n" ); document.write( "

Algebra.Com's Answer #838153 by math_tutor2020(3817) $\"\"$ $\"About$

You can put this solution on YOUR website!

\n" ); document.write( "Edit: RBryant you are clearly using a conditional proof. I would hope that a tutor such as yourself should know this basic logic concept.
\n" ); document.write( "If not then read this page
\n" ); document.write( "http://intrologic.stanford.edu/chapters/chapter_05.html
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\n" ); document.write( "\n" ); document.write( "The proof by tutor RBryant is correct, but the instructions specifically state to NOT use a conditional proof. \r
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\n" ); document.write( "\n" ); document.write( "The tutor Edwin has made an error.
\n" ); document.write( "The simplification and addition rules cannot apply to a piece of the expression, but rather must apply to the entire line.\r
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\n" ); document.write( "\n" ); document.write( "Refer to these rules of inference and replacement
\n" ); document.write( "https://logiccurriculum.com/2019/02/09/rules-for-proofs/\r
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\n" ); document.write( "\n" ); document.write( "This is how I would go about the derivation.
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Number	Statement	Line(s) Used	Reason
1	O -> (Q * N)
2	(N v E) -> S
:.	O -> S
3	~O v (Q * N)	1	Material Implication
4	(~O v Q) * (~O v N)	3	Distribution
5	~O v N	4	Simplification
6	(~O v N) v E	5	Addition
7	~O v (N v E)	6	Association
8	O -> (N v E)	7	Material Implication
9	O -> S	8,2	Hypothetical Syllogism

\n" ); document.write( "I used an arrow symbol in place of a horseshoe.
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