SOLUTION: 1. A v (B v C) 2. C ⊃ (D • E) 3. ~D / A v B

Question 1188620: 1. A v (B v C)
2. C ⊃ (D • E)
3. ~D / A v B

Answer by mccravyedwin(407) (Show Source): You can put this solution on YOUR website!


1. A ∨ (B ∨ C)
2. C ⊃  (D • E)
3. ~D                  / A ∨ B 

4. ~D ∨ ~E           3. Addition
5. ~(D • E)          4. DeMorgan's law
6. ~C                2,5, Modus Tollens
7. (A ∨ B) ∨ C       1, Association
8. C ∨ (A ∨ B)       9, Commutation
9. A ∨ B             8,6, Disjunctive Syllogism

Edwin

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