Question

determine o valor de x​

Answer 1

Aqui nós resolvemos através da lei dos cossenos:

$x^2=6^2+4^2-2\cdot 6\cdot 4\cdot cos(60\°)$

$x^2=36+16-48\cdot cos(60\°)$

$x^2=52-48\cdot \frac{1}{2}$

$x^2=52-\frac{48}{2}$

$x^2=52-24$

$x^2=28$

$x=\sqrt{28}$

$x=\sqrt{4\cdot 7}$

$x=2\sqrt{7}$