Question

(ab ≠ 0, a + b ≠ 0). Qual a resposta?

Answer 1

$\mathsf{\dfrac{a^{-2}+b^{-2}}{a^{-1}+b^{-1}}}\\\mathsf{\dfrac{\frac{1}{a^2}+\frac{1}{b^2}}{\frac{1}{a}+\frac{1}{b}}}$

$\mathsf{\dfrac{\frac{a^2+b^2}{a^2.b^2}}{\frac{a+b}{a.b}}}\\\mathsf{\dfrac{a^2+b^2}{a^2.b^2}\times\dfrac{ab}{a+b}=\dfrac{a^2+b^2}{a^2b+ab^2}}$