document.write( "Question 1006581: Q∨P
\n" ); document.write( "R→~P
\n" ); document.write( "R→Q\r
\n" ); document.write( "\n" ); document.write( "Here is what I put but I have not been able to pass correctly. Feedback is the proof solution is wrong. Any help would be great.\r
\n" ); document.write( "\n" ); document.write( "Solution
\n" ); document.write( "1) Q∨P
\n" ); document.write( "2) R→~P
\n" ); document.write( "3) Q (SIMP 1)
\n" ); document.write( "4) P (SIMP 2)
\n" ); document.write( "5) R (MP 2, 4)
\n" ); document.write( "6) R→Q (HS 3, 5)
\n" ); document.write( "Simplifying 1, we derive lines 3 and 4. Line 5 comes about as a natural deduction of line 2 and 4. Using DS rule, we derive line 6 from line 3 and 5.
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Algebra.Com's Answer #622712 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Simplification only works if you have a conjunction. NOT a disjunction.\r
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\n" ); document.write( "\n" ); document.write( "Here is how to do the derivation\r
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\n" ); document.write( "\n" ); document.write( "1) Q v P (given premise)
\n" ); document.write( "2) R -> ~P (given premise)
\n" ); document.write( ":. R -> Q (what we want to derive)
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\n" ); document.write( "3) P v Q (1, commutation)
\n" ); document.write( "4) ~~P v Q (3, double negation)
\n" ); document.write( "5) ~P -> Q (4, Material Implication)
\n" ); document.write( "6) R -> Q (2,5, hypothetical syllogism)\r
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