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

Ответ:

\[\frac{3^{\backslash x(x + 3)}}{x - 3} - \frac{x + 15^{\backslash x}}{x^{2} - 9} - \frac{2^{\backslash x^{2} - 9}}{x} =\]

\[= \frac{3x^{2} + 9x - x^{2} - 15x - 2x^{2} + 18}{x(x - 3)(x + 3)} =\]

\[= \frac{18 - 6x}{x\left( x^{2} - 9 \right)} = \frac{- 6(x - 3)}{x(x - 3)(x + 3)} =\]

\[= - \frac{6}{x(x + 3)} = - \frac{6}{x^{2} + 3x}.\]