tg 
= 
, 1 + tg 
= 
, cos (90 
- ) = sin ,
ctg = 
, 1 + ctg = 
, tg (90 - ) = ctg ,
sin + cos = 1, sin (90 - ) = cos , ctg (90 - ) = tg ,
tg (180 - ) = - tg , sin (180 - ) = sin ,
cos (180 - ) = - cos ; 
; 
.
11.
| 0
| 30
| 45
| 60
| 90
|
| sin | 0 | 
| 
| 
| 1 |
| cos | 1 |
|
|
| 0 |
| tg | 0 | 
| 1 | 
| ---- |
| ctg | ----- |
| 1 |
| 0 |
.
ٲ ʲ.
1. , ¢ . , .
2. , .
3. .
4. . , ¢ .
5. , .
6. . , ( ).
7. , .
8. - , - , .
9. - , .
|
 .
|
10. n :
1) n
180 
(n 2);
2) n , , 360 .
11. , . n - 
. 
12. .
13. ( ).
n .
15. . , , - , .
ʳ n -, :.
17. n -:
.
18. :
1. ³ , .
2. ³ .
19. :
| ʳ | (R) | (r) | |
| n | 
| 
| 
|
| n=3 |  
| 
| 
|
| n=4 | 
| 
| 
|
| n=6 | 
| 
| 
|
20. : 
, 
,
|
|
|
, 
- , 
, 
- .
21. :
| 
| 
| 
| 
|
| 
| 
| 
| 
|
.
1) :
S = ab
| 
S = ab sin
| 
S = ah
| 
S = d  d  sin 
|
S = a sin
| 
S = d d
| :
S = , S =  d ,
d =  , =  .
|  S = (a +b) h
|
2) :
S= ab , S= ab sin , S= ah,
S= a sin - , S = - ,
S = 
- ,
S = 
, ( ),
S = 
, a, b, c , R ,
S = pr, r , p .
3) - : S = d d sin , d ,d - , - .
4) - : S = pr, r , p .
5) :
, 
,
n -
- .
: 
,
, 
23. . 
, 
