Question

If A = {1, 2, 3, 4, 5, 6, 7, 8, 9}, determine the truth value of the following statement:

∀ x ∈ A, x + 5 < 12.

Answer 1

There is no x ∈ A which satisfies x + 5 < 12. So the given statement is false, hence its truth value is F.