Подставь функции в равенства

Формулы двойного угла.

• \(\sin \alpha \)
• \(\sin \alpha \)
• \(\sin \alpha\)
• \(\sin \alpha\)
• \(\cos \alpha\)
• \(\cos \alpha\)
• \(\cos \alpha\)
• \(\cos \alpha\)
• \(\tg \alpha\)
• \(\tg \alpha\)
• \(\tg \alpha\)
• \(\tg \alpha\)

\(\sin 2\alpha =\sin (\alpha +\alpha )=\) [ ] \(\cdot \) [ ] \(+\) [ ] \(\cdot \) [ ]

\(\cos 2\alpha =\cos (\alpha +\alpha )=\) [ ] \(\cdot \) [ ] \(-\) [ ] \(\cdot \) [ ]

\(\tg 2\alpha =\tg (\alpha +\alpha )=\) \((\) [ ] \(+\) [ ] \()\Big/\) \((1-\) [ ] \(\cdot \) [ ] \()\) .

Упростив равенства, получим:

1. \(\sin 2\alpha =2\sin \alpha \cos \alpha \) .
2. \(\cos 2\alpha =\cos^ 2\alpha -\sin ^2\alpha \) .
3. \(\tg 2\alpha =\dfrac{2\tg \alpha }{1-\tg^ 2\alpha }\) .