Решите уравнение (x-2)(x²+8x+16)=7(x+4) - вопрос №2816748851268 от shebkoch 08.09.2020 11:03

Question

Алгебра: Решите уравнение (x-2)(x²+8x+16)=7(x+4)

shebkoch · Answer

(x - 2) (x + 4)^2 = 7(x+4)(x - 2)*(x + 4)^2 - 7(x+4) = 0 (x+ 4) ((x - 2)(x + 4) - 7) = 0 (x+ 4) (x^2 + 2x - 8 - 7) = 0 (x + 4) ( x^2 + 2x - 15) = 0
x + 4 = 0 x1 = - 4
x^2 + 2x - 15 = 0 D = 4 + 4*15 = 64 x2 = ( - 2 + 8)/2 = 6/2 = 3;x3 = ( - 2 - 8)/2 = - 10/2 = - 5
ответ:- 5; - 4; 3