SOLUTION: This stuff is crazy O & I O -> (S v G) I -> ~G We have to show S

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Question 251009: This stuff is crazy
O & I
O -> (S v G)
I -> ~G
We have to show S
Found 2 solutions by drk, jim_thompson5910:
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
start with
O -> (S v G)
I -> ~G
(O n I) -> (S v G) n ~G -> S
If I remember correctly.

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
1.  O & I
2.  O -> (S v G)
3.  I -> ~G                / :. S
---------------------- 
4.  I & O                  1     Commutation
5.  O                      1     Simplification
6.  I                      4     Simplification
7.  ~G                     3,6   Modus Ponens
8.  S v G                  2,5   Modus Ponens
9.  S                      8,7   Disjunctive Syllogism