Упростите выражение (1/(a-b)-1/(a+b))*(a-b)/b.

\[\left( \frac{1^{\backslash a + b}}{a - b} - \frac{1^{\backslash a - b}}{a + b} \right) \cdot \frac{a - b}{b} = \frac{a + b - a + b}{(a - b)(a + b)} \cdot\]

\[\cdot \frac{a - b}{b} = \frac{2b(a - b)}{(a - b)(a + b) \cdot b} = \frac{2}{a + b}\]