Question 189545
Note: I'm going to use the & symbol for the •

So (Q • ~R) -> S = (Q & ~R) -> S


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1. P v Q
2.(Q & ~R) -> S
3. R -> P
4. ~P   / S
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5.  ~R                3,4   Modus Tollens
6.  Q                 1,4   Disjunctive Syllogism
7.  Q & ~R            5,6   Conjunction
8.  S                 2,7   Modus Ponens
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