Задача 55576 ...

5faf8cb4322e6f41f4eb6f49

14.11.2020 10:55:08

cos ^ 2 α (1+tg α )

5f3ea7e3faf909182968ddd9

14.11.2020 19:29:02

★

tg α =sin α /cos α

cos ^ 2 α (1+tg α )=[red]cos^2 α +cos α *sin α
[/red]

или:
1+tg^2 α =cos^2 α ⇒ cos^2 α =1/(1+tg^2 α )

cos ^ 2 α (1+tg α )=[red](1+tg α )/(1+tg^2 α )[/red]