Answer:
[tex] \frac{1 + \frac{a}{b} }{1 - \frac{ {a}^{2} }{ {b}^{2} } } \\\\ = \frac{ \frac{b + a}{b} }{ \frac{ {b}^{2} - {a}^{2} }{ {b}^{2} } } \\\\= \frac{b + a}{b} \times \frac{ {b}^{2} }{{b}^{2} - {a}^{2} } \\ \\ = \frac{b + a}{b} \times \frac{ {b}^{2} }{(b + a) (b - a)} \\ \\ = \frac{b}{b - a} [/tex]
