Question

разложите на множители (x+y)^3-(x-y)^3

Answer 1

(x+y)³-(x-y)³=(x+y-x+y)((x+y)²+(x+y)(x-y)+(x-y)²)=2y(x²+2xy+y²+x²-y²+x²-2xy+y²)=2y(3x²+y²)