trygonometria
Kaczorek: wiadomo, że α∊(0,90) oraz sin(90 stopni −α) + 3cosα = 1 oblicz √3tgα
20 lis 17:16
Eta:
α −− kąt ostry
| | 1 | |
sin(90o−α)= cosα to cosα+3cosα=1 ⇒4cosα=1 ⇒ cosα= |
| |
| | 4 | |
| | √15 | |
to sinα= √1−cos2α= ..... = |
| |
| | 4 | |
| | sinα | |
tgα= |
| =...= √15=√3*√5 |
| | cosα | |
zatem:
√3*tgα=...... =
3√5
20 lis 19:03