Question

Упростите выражение: 3/x-3 - x+15/x^2-9 - 2/x

Answer 1

$\frac{3}{x-3} -\frac{x+15}{x^{2}-9}-\frac{2}{x}=\frac{3}{x-3}-\frac{x+15}{(x-3)(x+3)}-\frac{2}{x}=\frac{3x(x+3)-x(x+15)-2(x^{2}-9)}{x(x-3)(x+3)}=\\\\=\frac{3x^{2}+9x-x^{2}-15x-2x^{2}+18}{x(x-3)(x+3)}=\frac{18-6x}{x(x-3)(x+3)}=\frac{6(3-x)}{x(x-3)(x+3)} =\boxed{-\frac{6}{x^{2}+3x}}$

Answer 2

3/3-х-х-15/(х-3)*(х+3)-2/х=
3х*(х+3)-х(х-15)-2(х-3)*(х+3)/х*(х-3)*(х+3)=
3х^2+9х-х^2+15х-2(х^2-9)/х*(х^2-9)=
3х^2+9х-х^2+15х-2х^2-18/х^3-9х=
0+24х+18/х^3-9х=
24х+18/х^3-9х