SOLUTION: Prove this 1. P∨Q 2. (Q∙~R)→S 3. R→P 4. ~P ∴ S I don't understand where to go from here,

Algebra ->  Proofs -> SOLUTION: Prove this 1. P∨Q 2. (Q∙~R)→S 3. R→P 4. ~P ∴ S I don't understand where to go from here,      Log On


   

Question 677564: Prove this
1. P∨Q
2. (Q∙~R)→S
3. R→P
4. ~P ∴ S
I don't understand where to go from here, I appreciate the help very much! I need to better understand the concept from this example
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
1.   P ∨ Q
2.   (Q ∙ ~R) → S
3.   R → P 
4.   ~P         ∴ S 
---------------------------
5.   ~R                3,4   Modus Tollens
6.   Q                 1,4   Disjunctive Syllogism
7.   Q ∙ ~R            6,5   Conjunction
8.   S                 2,7   Modus Ponens