Решите уравнение15 / (8-х) + 15 (8+х) = 4

15 / (8 - х) + 15 * (8 + х) = 4;

15 / (8 - x) * (8 - x) + 15 * (8 + x) * (8 - x) = 4 * (8 - x);

Раскроем скобки.

15 + 15 * (8^2 - x^2) = 4 * 8 - 4 * x;

15 + 15 * (64 - x^2) = 32 - 4 * x;

15 + 15 * 64 - 15 * x^2 = 32 - 4 * x;

15 + 960 - 15 * x^2 = 32 - 4 * x;

-15 * x^2 + 975 = 32 - 4 * x;

-15 * x^2 + 975 - 32 + 4 * x = 0;

-15 * x^2 + 4 * x + 943 = 0;

15 * x^2 - 4 * x - 943 = 0;

D = 4^2 - 4 * 15 * (-943) = 16 + 60 * 943 = 56 596;

x1 = (4 + √56 596) / 30;

x2 = (4 - √56 596) / 30.