Question

2part please!!!!!!!!!!!!!!!!!!!!!!

Answer 1

LHS,
$(a^{ - 1} + b^{ - 1} )^{ - 1} \\ = ( \frac{1}{a} + \frac{1}{b} )^{ - 1} \\ = (\frac{1}{ \frac{1}{a} + \frac{1}{b} } ) \\ = \frac{1}{ \frac{b + a}{ab} } \\ =\frac{ab}{a + b}$
= RHS
[Proven]

Hope it will help you .