Question

Cum se rezolva (a+b)•(1/a+1/b)

Answer 1

$(a+b)*( \frac{1}{a} + \frac{1}{b} )= \frac{a}{a} + \frac{a}{b} + \frac{b}{a} + \frac{b}{b} =$

$= 1+ \frac{a^2}{ab} + \frac{b^2}{ab} + 1 = \frac{a^2}{ab} + \frac{b^2}{ab} + \frac{2ab}{ab} =$

$=\frac{(a+b)^2}{ab}$