First let's rewrite it...
18a^2 + 20a + 8
Factor out a 2
2 (9a^2 + 10a + 4)
Answer:
expanded form: 5 * 5 * 5
value: 125
Step-by-step explanation:

One thing you could do is to expand either a factor of

or

, then expand the integrand. I'll do the first.
You have

which means the integral is equivalent to

Substitute

, so that

. This makes it so that the integral above can be rewritten in terms of

as

Now just use the power rule:

Back-substitute to get the antiderivative back in terms of

: