а. (x-4)×(x+2) = x^2 + 2x - 4x - 8 = x^2 - 2x - 8
б. (2x+1)×(5-x-4) = (2x+1)×(1-x) = 2x - 2x^2 + 1 - x = -2x^2 + 2
в. (3y-2x)×(y+6x) = 3y^2 + 18xy - 2xy - 12x^2 = 3y^2 + 16xy - 12x^2
г. (x+3)×(2*x^2 + 2x - 2) = 2x^3 + 2x^2 - 2x + 6x^2 + 6x - 6 = 2x^3 + 8x^2 + 4x - 6
а. (x-4)×(x+2) = x^2 + 2x - 4x - 8 = x^2 - 2x - 8
б. (2x+1)×(5-x-4) = (2x+1)×(1-x) = 2x - 2x^2 + 1 - x = -2x^2 + 2
в. (3y-2x)×(y+6x) = 3y^2 + 18xy - 2xy - 12x^2 = 3y^2 + 16xy - 12x^2
г. (x+3)×(2*x^2 + 2x - 2) = 2x^3 + 2x^2 - 2x + 6x^2 + 6x - 6 = 2x^3 + 8x^2 + 4x - 6