Question

(a-1) в квадрате*(a+1)+(a-1)*(a+1)

Answer 1

(a-1)²(a+1)  + (a-1)(a+1) = (a-1)(a-1)(a+1)  + 1(a-1)(a+1)=
= (a -1 +1)(a-1)(a+1) = a(a-1)(a+1) =
= а(а² - 1²) =  а³ -  а