Question

"If A is true, then B is false", is logically equivalent to which of the following?
I. If A is false, then B is true.
II. If B is false, then A is true.
III. If B is true, then A is false

• A. None of the above
• B. III only
• C. I and II only
• D. II and III only
• E. I, II and III

Answer 1

The correct option is B III only

Given if A is true ,then B is false

(I) if A is false ,then B is true not possible because A not logical repleted to B

(II) if B is false ,then A is true not possible because B not logical repleted to A

(III)If A is true then B is false, but then A is false. Which means B is true, but then A is true. Which means B is false.

Then (III) is write