$\left(2\pi k,\ \pi+2\pi k\right)$

$\left(-\frac{\pi}{2}+2\pi k,\ \frac{\pi}{2}+2\pi k\right)$

$\left(\frac{\pi}{2}+2\pi k,\ \frac{3\pi}{2}+2\pi k\right)$

$\left(\pi k,\ \frac{\pi}{2}+\pi k\right)$

$\pi+2\pi k,\ k\ \epsilon\ Z$

$\pi k,\ k\ \epsilon\ Z$

$2\pi k,\ k\ \epsilon\ Z$

$\frac{\pi}{2}+\pi k,\ k\ \epsilon\ Z$

$x\ =-\frac{\pi}{2}+2\pi k,\ k\ \epsilon\ Z$

$x\ =2\pi k,\ k\ \epsilon\ Z$

$x\ =\ \frac{\pi}{2}+\pi k,\ k\ \epsilon\ Z$

$x\ =\ \frac{\pi}{2}+2\pi k,\ k\ \epsilon\ Z$

R

[-1; 1]

0

Z

R

0

Q

[-1; 1]

1

-2

2

0

-1

5

1

9

cos145⁰, cos75⁰, cos22⁰

cos75⁰, cos145⁰, cos22⁰

cos145⁰, cos22⁰, cos75⁰

cos22⁰, cos75⁰, cos145⁰

ctg 72⁰, ctg 13⁰ , ctg 107⁰

ctg 13⁰ , ctg 107⁰ , ctg 72⁰

ctg 13⁰ , ctg 72⁰, ctg 107⁰

ctg 107⁰, ctg 72⁰, ctg 13⁰

y = cos 3x

y = sin 3x

y = cos(x/3)

y = tg x