(2x+1)^2+(2x-1)(2x+1)=?
4x^2 + 4x + 1 + 4x^2 -1 = 8x^2 + 4x = 4x(2x+1)
(2x+1)(2x+1+2x-1)=(2x+1)4x=8x^2+4x