Question

(x.x la a 2 a .x la a 3a . x la a 4a):x la a 10 . x=?

(2x+1) la a 2 a - (2x-1)la a 2 a

Answer 1

$(x* x^{2} * x^{3} * x^{4} ): x^{10}= x^{10}: x^{10}=1. \\ \\ (2x+1)^{2} -(2x-1)^{2} =[(2x+1)+(2x-1)][(2x+1)-(2x-1)]= \\ \\ =4x*2=8x.$