trygonometria
h20: jak przekształcić
cos2(π6+x) + cos2(π6−x) ?
24 mar 18:18
h20: jakaś wskazówka?
24 mar 18:24
Mila: cos(α+β)=cosα cosβ−sinα sinβ
cos(α−β)=cosα cosβ+sinα sinβ
| | π | | π | | π | | π | |
[cos |
| cosx−sin |
| sinx]2+[cos |
| cosx+sin |
| sinx]2= |
| | 6 | | 6 | | 6 | | 6 | |
| | √3 | | 1 | | √3 | | 1 | |
=( |
| cosx− |
| sinx)2+( |
| cosx+ |
| sinx)2= |
| | 2 | | 2 | | 2 | | 2 | |
dokończ
24 mar 20:37