SOLUTION: Prove directly, no Conditional Proof or Indirect Proof 1. M ⊃ ~ C 2. ~C ⊃ ~ A 3. D v A / ~ M v D

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Question 1193811: Prove directly, no Conditional Proof or Indirect Proof
1. M ⊃ ~ C
2. ~C ⊃ ~ A
3. D v A / ~ M v D





Answer by math_tutor2020(3816) About Me  (Show Source):
You can put this solution on YOUR website!

Hint:
D v A
A v D
~~A v D
~A ⊃ D
I used the material implication rule on the fourth step shown above.

Another hint:
You'll use the hypothetical syllogism rule exactly twice.
Think of it like a chain of dominos. One statement leads to another which points to another. You'll then use the material implication rule one final time.