Question

Equacoes trigonometricas, ajuda!

Answer 1

$\sin^22x-\sin2x=0\\ \\ \sin2x\;(\sin2x-1)=0\\ \\ \sin 2x =0\vee \sin 2x = 1\\ \\ \displaystyle 2x\in\{0;\pi\}\vee 2x\in\left\{\frac{\pi}{2}\right\}\\ \\ x\in\left\{0;\frac{\pi}{2}\right\}\vee x\in\left\{\frac{\pi}{4}\right\}\\ \\ x\in\left\{0;\frac{\pi}{2}\right\}\cup\left\{\frac{\pi}{4}\right\}\\ \\ \\ \boxed{x\in\left\{0;\frac{\pi}{2};\frac{\pi}{4}\right\}}$

El número de raíces es 3