Question

Se f(x) = 1/(x² + 1) , quanto vale f(indice 4 raiz de 7) ?

Answer 1

$f(x) = \frac{1}{x^2+1} \\ \\ f( \sqrt[4]{7}) = \frac{1}{( \sqrt[4]{7})^2 +1 } \\ \\ f( \sqrt[4]{7}) = \frac{1}{ \sqrt[]{7} + 1} \\ \\ f( \sqrt[4]{7}) = \frac{1. (\sqrt{7}-1) }{( \sqrt{7}+1) . (\sqrt{7} - 1) } \\ \\ f( \sqrt[4]{7}) = \frac{ \sqrt{7}-1 }{6}$