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Math Help - cant solve this problem (proof by contradiction)

  1. #1
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    cant solve this problem (proof by contradiction)

    i tried to solve this question 100 times but could n't get the right answer
    plz help guys
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  2. #2
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    \begin{array}{llr}<br />
   1 & {\left( {S \wedge R} \right) \to Q} & {}  \\<br />
   2 & {\neg R \to \neg P} & {}  \\<br />
   3 & {S \wedge P} & {}  \\<br />
   4 & {\neg Q} & {\text{assume}}  \\<br /> <br />
 \end{array}
    <br />
\begin{array}{llr}<br />
   5 & {\neg \left( {S \wedge R} \right)} & {1,4}  \\<br />
   6 & {\neg S \vee \neg R} & 5  \\<br />
   7 & S & 3  \\<br />
   8 & {\neg R} & 6  \\<br />
   9 & {\neg P} & {2,8}  \\<br />
   {10} & P & 3  \\<br />
   {} & {P \wedge \neg P} & {8,9  \text{ contradiction}}  \\ \end{array}
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