Cho $ \alpha +\beta +\gamma = \pi $. Khi đó:

Question

Cơ bản

4 câu trả lời

Answer 1

$|cot (2\alpha +2\beta)= \cot 2\gamma $

Answer 2

$\tan ( 2\alpha +2\beta)= \tan2 \gamma $

Answer 3

$\cos (2 \alpha +2\beta )= \cos2 \gamma $

Answer 4

$\sin (2\alpha +2\beta )= \sin 2\gamma $