Question

ПОМОГИТЕ ПОЖАЛУЙСТА
как это делать???

Answer 1

$cos(x+\dfrac{\pi}{3})\geq -\dfrac{1}{2}\\\\\\-\dfrac{2\pi}{3}+2\pi n\leq x+\dfrac{\pi}{3}\leq \dfrac{2\pi}{3}+2\pi n\; ,\; n\in XZ\\\\\\-\dfrac{2\pi}{3}-\dfrac{\pi}{3}+2\pi n\leq x\leq\dfrac{2\pi}{3}-\dfrac{\pi}{3}+2\pi n\; ,\; n\in Z\\\\\\-\pi +2\pi n\leq x\leq \dfrac{\pi}{3}+2\pi n\; ,\; n\in Z\\\\\\x\in [\, -\pi +2\pi n\, ;\, \dfrac{\pi}{3}+2\pi n\, ] \; ,\; n\in Z$

Answer 2

cos(x+π/3)≥-1/2

решение во вложении