Sine and cosine from rotating vector
The unit circle and the graphs of the sine and cosine functions are related. Check out this simulation to find out how one relates to the other.
Note:
Click the START button to see the animation. In the right window, select the sine check box to view an animation of the sine function,
Move the sliders to change the frequency and phase on the left window. Also, it is possible to edit a new amplitude into box A.
Repeat the same with cosine function.