Unit Circle: The Tangent Function
- Author:
- Brian Sterr
This sketch shows how we can create a function for tangent.
As a point goes around the unit circle, we can see how the different ratios change based on the angle, given here as and measured in radians.
First, select Tangent and then Animate. At each of the points on the traced out curve, the -coordinate represents the angle and the -coordinate represents the sine of the angle.
The tangent of the angle can be found on using the point on the unit circle:
In other words, the tangent gives us the slope of the terminal side of the angle.
Also, if we were to draw two lines tangent to our unit circle at and , then the leg of the right triangle formed with the radius from to and the terminal side of would have a length of .