Сверь числа и знаки с фото.
Упражнения А Решите уравнения (19.1—19.11): 19.1. 1) \(\cos x=\frac{\sqrt{3}}{2}\); 2) \(\cos x=\frac{\sqrt{2}}{2}\); 3) \(\cos x=\frac{1}{2}\); 4) \(\cos x=-\frac{\sqrt{3}}{2}\); 5) \(\cos x=0\); 6) \(\cos x=1\). 19.2. 1) \(\sin x=\frac{\sqrt{3}}{2}\); 2) \(\sin x=\frac{\sqrt{2}}{2}\); 3) \(\sin x=-\frac{1}{2}\); 4) \(\sin x=-\frac{\sqrt{3}}{2}\); 5) \(\sin x=0\); 6) \(\sin x=-\frac{\sqrt{2}}{2}\). 19.3. 1) \(\operatorname{tg} x=3\); 2) \(\operatorname{tg} x=-2\); 3) \(\operatorname{tg} x=-\frac{\sqrt{3}}{3}\); 4) \(\operatorname{ctg} x=-\frac{\sqrt{3}}{2}\); 5) \(\operatorname{ctg} x=0\); 6) \(\operatorname{ctg} x=-3\).
Все ответы при \(k\in\mathbb{Z}\).
19.1
- \(x=\pm\frac{\pi}{6}+2\pi k\);
- \(x=\pm\frac{\pi}{4}+2\pi k\);
- \(x=\pm\frac{\pi}{3}+2\pi k\);
- \(x=\pm\frac{5\pi}{6}+2\pi k\);
- \(x=\frac{\pi}{2}+\pi k\);
- \(x=2\pi k\).
19.2
- \(x=(-1)^k\frac{\pi}{3}+\pi k\);
- \(x=(-1)^k\frac{\pi}{4}+\pi k\);
- \(x=(-1)^{k+1}\frac{\pi}{6}+\pi k\);
- \(x=(-1)^{k+1}\frac{\pi}{3}+\pi k\);
- \(x=\pi k\);
- \(x=(-1)^{k+1}\frac{\pi}{4}+\pi k\).
19.3
- \(x=\operatorname{arctg}3+\pi k\);
- \(x=-\operatorname{arctg}2+\pi k\);
- \(x=-\frac{\pi}{6}+\pi k\);
- \(x=\operatorname{arcctg}\left(-\frac{\sqrt{3}}{2}\right)+\pi k\);
- \(x=\frac{\pi}{2}+\pi k\);
- \(x=\operatorname{arcctg}(-3)+\pi k\).