Mark M. answered 04/26/22
Retired math prof. Very extensive Precalculus tutoring experience.
The integral is equivalent to limb→∞ ∫(from 1 to b) [9x-1.5]dx
= limb→∞ [-18/√x](from 1 to b)
= limb→∞ [-18/√b + 18] = 0 + 18 = 18
The integral converges to 18.