Question

dado sen x= 1/3, com o<x<π/2, calcular cos x.​

Answer 1

Resposta:

cos x = 2√2 /3

Explicação passo-a-passo:

$cos^{2} x+sen^2x=1\\cos^2x=1-\frac{1}{9}\\cos^2x=\frac{8}{9}\\cosx=\sqrt{\frac{8}{9}}=\frac{2\sqrt{2}}{3}$