Evaluate the following integrals:

Question

Philoid · Accepted Answer

Here (4x + 2) can be written as 2(2x + 1).

Now assume, x² + x + 1 = t

d(x² + x + 1) = dt

(2x + 1)dx = dt

⇒

But t = x² + x + 1

⇒ .