1. (X v B) --> ~J       Premise

2. S --> J              Premise

3. X                    Premise

// show ~S 

4. X v B                3, Addition (ADD)

5. ~J                   4,1,  Modus Ponens (MP)

6. ~S                   5,2,  Modus Tollens (MT)

** Done ** 

RELATED QUESTIONS

1.  ~J v ~L
2.  ~(J * L) -> ~M
3.  ~E v (M v ~S)           /  ~(S * E)  (answered by jim_thompson5910)

Solve the following Proof:

1. G => (S&T) 
2. (S v T) => J
3. G     /J  (answered by math_helper)

 1. [J v (N & T)]
2.  ~(~T -> S)     /     J


i need help solving this proof 

 (answered by guest567)

How would you prove this argument valid ? 
1. A > H
2. G > S
3. ~ K > (A v G) 
4. ~ K  (answered by math_helper)

1.(D v L) -> ~S
2.(D & J)
3.(S v P) / P 


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I am having trouble solving the following propositional logic proofs. 

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Hi, I need help with finishing these proofs for my PHI class I am so confused! :(

[1]
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Example:
1.	A
2.	A>B	/ B
3.	B	1,2 MP		←You add this line


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