Question

Упростите выражение: а) (x + 2)(x - 5) - (x + 4)^2 б) (5x - y)(5x + y) + 3y^3 - 25x^2

Answer 1

а) (x + 2)(x - 5) - (x + 4)^2 =x^2+2x-5x-10-x^2-8x-16=-11x-26
б) (5x - y)(5x + y) + 3y^3 - 25x^2=25x^2-y^2+3y^3-25x^2=3y^3-y^2