Question

ALGUÉM DE BOM CORAÇÃO ME AJUDA???

Answer 1

$x^2 + \frac{1}{x^2} = ~?$

Se:

$x-\frac{1}{x}=\frac{9}{5} ~~(eleve~~ao~~quadrado~~ambos~~os~~lados)\\\\\\(x-\frac{1}{x})^2=(\frac{9}{5})^2\\\\x^2-2.x.\frac{1}{x} + \frac{1^2}{x^2}=\frac{81}{25} \\\\x^2-2+\frac{1}{x^2} = \frac{81}{25}\\\\x^2+\frac{1}{x^2} = \frac{81}{25} + 2\\\\x^2+\frac{1}{x^2} = \frac{81}{25} + \frac{50}{25} \\\\x^2+\frac{1}{x^2} = \frac{131}{25}$

Resposta: 131/25