Question 1028652
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1. (Av~B)&#8835;[(A+C)&#8835;B]
2. ~B              /  A&#8835;~C

3. [(Av~B)•(A&C)]&#8835;B          1, Importation
4. ~[(Av~B)•(A•C)]           3,2 Modus Tollens
5. ~(Av~B)v~(A•C)            4, DeMorgan's law
6. ~BvA                      2, Addition
7. Av~B                      6, Commutation
8. ~~(Av~B)                  7, Double negation
9. ~(A•C)                    5,8, Disjunctive syllogism
10. ~Av~C                    9, DeMorgan's law
11. A&#8835;~C                     10, Material implication

Edwin</pre></b>