b) (4x^2 + 2xy + y^2)(2x – y).
b) (4x2 + 2xy + y2)(2x – y).
b) (4x2 + 2xy + y2)(2x – y) = (2x – y)[(2x)2 + 2xy + y2]
= (2x)3 – y3 = 8x3 – y3.