Trigonometry - Identities
Using The Identity
| sinθ | |
| tanθ = | |
| cosθ |
Example
Show that cosθ tanθ = sinθ
Use substitution
| sinθ | |
| tanθ = | |
| cosθ |
| sinθ | |
| cosθ tanθ = cosθ | |
| cosθ |
Cancel by cosθ
cosθ tanθ = sinθ
The above example is shown as the first example on the video below
