Question

What is the coefficient of x2 in the expansion of (x + 2)3?

Answer 1

One way is that you can just factor it out: (x+2)(x+2)(x+2)
For the first pair, you get $x^2+4x+4$.
Then do $(x^2+4x+4)$*$(x+2)$
That will be $x^3+6x^2+12x+8$
So the answer is 6