[tex]\frac{2b}{a} + \frac{a+b}{a-b} : \frac{a^{2} + ab}{ab - b^{2} } = \frac{2b}{a} + \frac{a + b}{a-b} * \frac{ab - b^{2} }{a^{2} + ab } = \frac{2b}{a} + \frac{a+b}{a-b} * \frac{b* (a-b)}{a* (a+b)} = \frac{2b}{a} + \frac{b}{a} = \frac{3b}{a}[/tex]