SOLUTION: (~RvD)-->~(F•G)/(F•R)-->S/F•~S/:.~(SvG)

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Question 964275: (~RvD)-->~(F•G)/(F•R)-->S/F•~S/:.~(SvG)
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
1. (~RvD)-->~(F•G)
2. (F•R)-->S
3. F•~S
     ∴ ~(SvG)

4. ~S                    3. Simp. 
5. ~S-->~(F•R)           2, CP
6. ~(F•R)                5,4 MP
7. ~Fv~R                 6, DM
8. F                     3, Simp.
9. ~~F                   8, DN
10. ~R                   7,9 DS
11. ~~(F•G)-->~(~RvD)    1, CP
12. F•G-->~(~RvD)        11, DN
13. F•G-->~~R•~D         12, DM
14. F•G-->R•~D           13, DN
15. ~(R•~D)-->~(F•G)     14, CP
16. ~Rv~~D-->~Fv~G       15, DM
17. ~RvD-->~Fv~G         16, DN 
18. ~RvD                 10, Addition
19. ~Fv~G                17, 18, MP
20. ~G                   19,9, DS
21. ~G•~S                20,4 Conjunction
22. ~(GvS)               21, DM 

Edwin