Question

(x+1)*(x-x+1)-x(x-1) при х=-2

Answer 1

$(x + 1) \times (x - x + 1) - x(x - 1) = \\ (x + 1) \times 1 - {x}^{2} + x = \\ x + 1 - {x}^{2} + x = \\ 2x - {x}^{2} + 1 \\ x = - 2 \\ 2 \times ( - 2) - ( - 2) ^{2} + 1 = \\ - 4 - 4 + 1 = - 8 + 1 = - 7$