| 1 | ||
b)tgx+ctgx= | ||
| sinxcosx |
| sinx | 1−cosx | |||
c) | = | |||
| 1+cosx | sinx |
| sinx | 1−cosx | 2 | ||||
d) | + | = | ||||
| 1−cosx | sinx | sinx |
| ctgx−tgx | 1 | 1 | ||||
e) | = | − | ||||
| sinx+cosx | sinx | cosx |
| sin2x | ( 1 − cosx) 2 | |||
d) L = | + | = | ||
| ( 1 − cosx ) sin x | ( 1 − cosx ) sin x |
| sin2x + 1− 2cosx + cos2x | |
= | |
| sin x ( 1 − cosx) |
| 2 − cos x | 2( 1 − cosx) | 2 | |||
= | = | ||||
| sin x ( 1 − cos x) | sin x ( 1− cosx) | sinx |