Question

Se cos x= -3√2 /5 e tg x= -√14 /6, qual o valor de sen x?

Answer 1

$\dfrac{\text{sen}~x}{\text{cos}~x}=\text{tg}~x$

$\dfrac{\text{sen}~x}{\frac{-3\sqrt{2}}{5}}=\dfrac{-\sqrt{14}}{6}$

$\text{sen}~x=\left(\dfrac{-3\sqrt{2}}{5}\right)\cdot\left(\dfrac{-\sqrt{14}}{6}\right)$

$\text{sen}~x=\dfrac{3\sqrt{28}}{30}=\dfrac{2\sqrt{7}}{10}=\dfrac{\sqrt{7}}{5}$