| 7 | 49 | |||
sin α+cos α= | (sin α+cos α)2= | |||
| 13 | 169 |
| 49 | ||
sin2α+2sin α*cos α+cos2α= | ||
| 169 |
| 49 | ||
1+2sin α*cos α= | ||
| 169 |
| 49 | 169 | 120 | ||||
2sin α*cos α= | − | =− | ||||
| 169 | 169 | 169 |
| 120 | ||
(sin α−cos α)2=sin2α−2sin α*cos α+cos2α=1−2sin α*cos α=1−(− | )= | |
| 169 |
| 289 | ||
= | ||
| 169 |
| 17 | 17 | |||
sin α−cos α= | lub sin α−cos α=− | |||
| 13 | 13 |