Question

2(x^2+2y)(x^3+7y)-2x^2(x^3-3y)

Answer 1

Ответ:

$2(x^2+2y)(x^3+7y)-2x^2(x^3-3y)=\\\\=2(x^5+7x^2y+2x^3y+14y^2)-2x^5+6x^2y=\\\\=20x^2y+4x^3y+28y^2$