Ответ:
Используем табличные значения и формулы приведения:
- \(\sin 120^\circ=\sin(180^\circ-60^\circ)=\sin 60^\circ=\frac{\sqrt{3}}{2}\);
- \(\operatorname{ctg}60^\circ=\frac{1}{\operatorname{tg}60^\circ}=\frac{1}{\sqrt{3}}=\frac{\sqrt{3}}{3}\);
- \(\cos150^\circ=\cos(180^\circ-30^\circ)=-\cos30^\circ=-\frac{\sqrt{3}}{2}\);
- \(\cos120^\circ=\cos(180^\circ-60^\circ)=-\cos60^\circ=-\frac{1}{2}\);
- \(\operatorname{tg}60^\circ=\sqrt{3}\);
- \(\operatorname{tg}45^\circ=1\).
Ответ: \(\sin120^\circ\) — \(\frac{\sqrt{3}}{2}\); \(\operatorname{ctg}60^\circ\) — \(\frac{\sqrt{3}}{3}\); \(\cos150^\circ\) — \(-\frac{\sqrt{3}}{2}\); \(\cos120^\circ\) — \(-\frac{1}{2}\); \(\operatorname{tg}60^\circ\) — \(\sqrt{3}\); \(\operatorname{tg}45^\circ\) — \(1\).
