Lecture 4/1 ñ Summary
There are many functions where the variable can be regarded as an ANGLE.
One way of measuring an angle is that derived from the radius of the circle. This is called RADIAN measure.
From the UNIT CIRCLE, we can see that the SINE of an angle is the height of a triangle drawn inside the circle. Sine(¯) then becomes a function depending on the size of the angle ¯.