$$\sin (\alpha \pm \beta )=\sin \alpha \cos \beta \pm \cos \alpha \sin \alpha$$
$$\cos (\alpha \pm \beta )=\cos \alpha \cos \beta\mp \sin \alpha \sin \alpha$$
$$ tg (\alpha \pm \beta )=\frac{ tg \alpha \pm tg \beta }{1\mp tg \alpha tg \beta }$$
$$ctg (\alpha \pm \beta )=\frac{ctg\alpha\cdot ctg \beta \mp 1 }{ctg\beta \pm ctg \alpha}$$
2010-12-11 • Просмотров [ 1534 ]
