1. (3x(x-3)+3(x+3)-2x*x)/x(x+3)(x-3) = (3x*x-9x+3x+9-2x*x)/x(x+3)(x-3) = (x*x-6x+9)/x(x+3)(x-3) = ((x-3)(x-3))/x(x-3)(x+3) = 1/x(x+3)
(x+2)(x²+x-12)>0
x²+x-12 = 0
D = 1+48 = 49 = 7²
x(1) = (-1+7) / 2 = 3
x(2) = (-1-7) / 2 = -4
(x+2)(x+4)(x-3)>0
- + - +
-----o-----o-----o------>x
-4 -2 3
x∈(-4; -2)U(3; +∞)
Раскрываем скобки:
у²-у+8у-8 = 1+7у
Упростим:
у²+7у-8-1-7у=0
у²-9=0
у²=9
у = +- 3