Question

simplify [x^-1+y^-1]^-1

Answer 1

$\frac{1}{ {x}^{ - 1 } + {y}^{ - 1} } \\ \\ = > \frac{1}{ \frac{1}{x} + \frac{1}{y} } \\ \\ => \frac{1}{ \frac{x + y}{xy} } \\ \\ => \frac{xy}{x + y}$