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Premises:
≈P→(Q→≈W)
≈S→Q
≈T
P→T
W→S
Conclusion:
W→S
I don’t really understand how to do this and I have a test coming up so any help would be greatly appreciated.
Solution
You have W–>S as part of the given premises AND the CONCLUSION we are trying to prove.
I will ignore it.
Since ~T is given and P–>T, then ~P follows by contrapositive.
It follows that Q–>~W per the given premises.
However, ~S –> Q and Q–>~W, so ~S –> Q —> ~W.
Then ~S –> ~W
Therefore W–> S by contra-positive