$\mathrm{\pi }$

$-\mathrm{\pi }$

$\frac{\mathrm{\pi }}{2}$

$-\frac{\mathrm{\pi }}{2}$

$2\mathrm{n\pi }\pm \frac{\mathrm{\pi }}{3}$

$\mathrm{n\pi }\pm \frac{\mathrm{\pi }}{3}$

$\mathrm{n\pi }\pm \frac{\mathrm{\pi }}{6}$

$2\mathrm{n\pi }\pm \frac{\mathrm{\pi }}{6}$

2

3

4

5

$7n^2+2$

$x^2-2x+3$

$x^2-2n+1$

$2x^2+7$

$\frac{-x}{y}$

$\frac{n}{y}$

$\frac{y}{x}$

$\frac{-y}{x}$

$\frac{-7}{13}$

$\frac{8}{9}$

$\frac{-8}{9}$

$\frac{7}{13}$

$1+\frac{1}{x^2}$

$\frac{1}{x^2}$

$1-\frac{1}{x^2}$

$-\frac{1}{x^2}$

4

6

7

8

9

8

7

10

20.5

24.5

25

30

$\frac{3}{2}$

$\frac{11}{6}$

$\frac{2}{3}$

$\frac{3}{4}$

14

16

15

18

-3

5

9

$\frac{3}{2}$

$\frac{2}{3}$

2

$\frac{1}{2}$

x = b

y =0

x =0

y = b

$\frac{3}{4}$

$\frac{4}{3}$

$-\frac{4}{3}$

$\frac{1}{4}$

$\tan 10°$

$\sqrt{3}$

$-\sqrt{3}$

$\frac{1}{\sqrt{3}}$

$\frac{2}{12}$

$\frac{4}{14}$

$\frac{1}{5}$

$\frac{1}{3}$

$30°$

$45°$

$60°$

$90°$

2

3

4

5