Respuesta :

devishri1977

Answer:

Step-by-step explanation:

[tex]\frac{1}{a}-\frac{1}{b} =\frac{1*b}{a*b}-\frac{1*a}{b*a}\\\\=\frac{b}{ab}-\frac{a}{ab}\\\\=\frac{b-a}{ab}\\\\\\(\frac{1}{a}-\frac{1}{b})^{-1} = (\frac{b-a}{ab})*{-1}\\\\=\frac{ab}{b-a}[/tex]