Find interval where f(x) is integrable

Question

Determine the interval on which f(x) = ln(x) is integrable.

Question options:

1)	(0, ∞)
2)	[0, ∞)
3)	(-∞, 0) U (0, ∞)
4)	All reals

Answer 1

∫ln x dx = x ln x - x

Therefore, the answer is #1