Question 1140965
<pre>
How would you prove this argument valid ? 
1. A > H
2. G > S
3. ~ K > (A v G) 
4. ~ K & D
5.( H v S)> J   /J 

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1. A > H
2. G > S
3. ~ K > (A v G) 
4. ~ K & D
5.( H v S)> J
6. ~K         4, SIMP
7. A v G      6,3  MP 
8.:: A        Conditional Proof (CP) assumption #1
9.:: H        8,1  MP
10.:: H v S   9  ADD
11.:: G       CP assumption #2
12.:: S       12,2 MP
13.:: S v H   12 ADD
14.:: H v S   13 COMM
15.:: A v G --> H v S   8-14 Proof by Cases (PBC)
16. A v G --> H v S     8-15 CP
17. H v S     7,16  MP
15. J         17,5  MP


EDITED 5/15:  Corrected line 17 from "5,16  MP"  to  "7,16  MP"