a )(2x+7)(3x-1) - (5x-1)(x+3) = (x+1)²
б)(x-2)³ + (x+2)³ = 2)x-3)(x³+3x+9)

б) где ?

a) (2x+7)(3x-1) - (5x-1)(x+3) = (x+1)^26x^2 - 2x + 21x - 7 - 5x^2 - 15x + x + 3 = x^2 + 2x + 1x^2 + 5x - 4 = x^2 + 2x + 1x^2 - x^2 + 5x - 2x - 4 - 1 = 03x - 5 = 03x = 5x = 5/3