Question 297359
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1.  F -> G
2.  F v G            :. G
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3.  G v F                 2      Commutation
4.  ~~G v F               3      Double Negation
5.  ~G -> F               4      Material Implication
6.  ~G -> G               5,1    Hypothetical Syllogism
7.  ~~G v G               6      Material Implication
8.  G v G                 7      Double Negation
9.  G                     8      Tautology
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