Question 243966
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1.  (R v S) -> (T & U)
2.  ~R -> (V -> ~V)
3.  ~T                        /Therefore ~V
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4.  ~T v ~U                             3         Addition
5.  ~(T & U)                            4         De Morgan's Law
6.  ~(R v S)                            1,5       Modus Tollens
7.  ~R & ~S                             6         De Morgan's Law
8.  ~R                                  7         Simplification
9.  V -> ~V                             2,8       Modus Ponens
10. ~V v ~V                             9         Material Implication
11. ~V                                  10        Tautology
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