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Question: Need help solving this proof!?
Trying to figure out how to justify this proof with the rules used!. also!.!.!. do you know any websites that may help me in the future!?

1!. (J v K) > ~L
2!. L / ~J
3!. ~~L > ~(J v K)
4!. L > ~(J v K)
5!. ~(J v K)
6!. ~J & ~K
7!. ~J
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Best Answer - Chosen by Asker:
1!. (J ∨ K) ? ~L
2!. L / ~J

3!. ~~L ? ~(J ∨ K) !.!.!.!. 1 Transposition
4!. L ? ~(J ∨ K) !.!.!.!.!.!.!. 3 Double Negative
5!. ~(J ∨ K) !.!.!.!.!.!.!.!.!.!. 2,4 Modus Ponens (Affirming the Antecedent)
6!. ~J & ~K !.!.!.!.!.!.!.!.!.!. 5!. DeMorgan's Rule
7!. ~J !.!.!.!.!.!.!.!.!.!.!.!.!. 6 Simplification (Conjunct Elimination)

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Same conclusion could have been reached in one fewer steps, using simpler rules!.!.!.

1!. (J ∨ K) ? ~L
2!. L / ~J

3!. ~~L !.!.!.!.!.!.!.!.!. 2 Double Negative
4!. ~(J ∨ K) !.!.!.!.!.!.!. 1,3 Modus Tollens (Denying the Consequence)
5!. ~J & ~K !.!.!.!.!.!.!.!.!.!. 4!. DeMorgan's Rule
6!. ~J !.!.!.!.!.!.!.!.!.!.!.!.!. 5 Simplification (Conjunct Elimination)Www@QuestionHome@Com