Question

Нужно с решением: решите неравенство

Answer 1

$sin4x\geq sin2x\\2sin2xcos2x-sin2x\geq0\\sin2x(2cos2x-1)\geq0\\ \left \{ {{sin2x\geq0} \atop {2cos2x-1\geq0}} \right. \\1)2sin2x\geq0\\sin2x\geq0\\0\leq2x\leq\pi\\2\pi k\leq 2x\leq\pi+2\pi k,k\in z\\\pi k\leq x\leq \frac{\pi}{2}+\pi k,k\in z\\ 2)2cos2x-1\geq0\\cos2x\geq \frac{1}{2}\\ -\frac{\pi}{3}\leq 2x\leq \frac{\pi}{3}\\ -\frac{\pi}{3}+2\pi n\leq2x\leq \frac{\pi}{3}+2\pi n,n\in z\\ -\frac{\pi}{6}+\pi n\leqx\leq \frac{\pi}{6}+\pi n,n\in z$
$\left \{ {{sin2x\leq0} \atop {2cos2x-1\leq0}} \right.\\1)sin2x\leq0\\\pi\leq2x\leq 2\pi\\\pi+2\pi k\leq2x\leq\ 2\pi+2pi k,k\in z\\ 1+\pi k\leq x\leq \pi+\pi k,k\in z\\2)2cos2x-1\leq0\\cos2x\leq \frac{1}{2}\\ \frac{\pi}{3}\leq2x\leq \frac{5\pi}{3}\\ \frac{\pi}{3}+2\pi n\leq 2x\leq \frac{5\pi}{3} +2\pi n,n\in z\\ \frac{\pi}{6}+\pi n\leq x\leq \frac{5\pi}{6}+\pi n, n\in z$
общее решение уравнения
$x\in[\pi m; \frac{\pi}{6}+\pi m ],m\in\mathbb{Z}$;$x\in[1+\pi m;\pi+\pi m],m\in\mathbb{Z}$