Tried posting this elsewhere but running out of time

2x^3 + x^2 - 2x - 1

(2x^3 + x^2) + (2x + 1)

x^2( 2x + 1) + 1(2x + 1) found the common factor(not sure if thats the right term)

So my final answer would be this which is wrong, anyone got a solution?

(2x + 1)(x^2 +1)