第11章 11.8

(1)

sin450°=sin90°=1\sin 450° = \sin 90° = 1

(2)

sin(765°)=sin(45°)=12\sin(-765°) = \sin(-45°) = -\frac{1}{\sqrt{2}}

(3)

cos2130°=cos330°=32\cos 2130° = \cos 330° = \frac{\sqrt{3}}{2}

(4)

cos(120°)=12\cos(-120°) = -\frac{1}{2}

(5)

tan420°=tan60°=3\tan 420° = \tan 60° = \sqrt{3}

(6)

tan(225°)=1\tan(-225°) = -1

解説: r31bn1z