Question

resposta explicativa passo a passo, por favor.

Answer 1

$x+\dfrac{1}{x}=3\\ \\ \\ \left(x+\dfrac{1}{x}\right)^2=3^2\\ \\ \\ x^2+2+\dfrac{1}{x^2}=9\\\\\\ x^2+\dfrac{1}{x^2}=7\\\\\\ \boxed{x^2+\dfrac{1}{x^2}-2=5}$