2. (10 points) In Chapter 5, we used the concept of terminal point on the unit circle to define the trigonometric functions as functions of real numbers. Suppose we have a circle of radius r> 0 centered at the origin. Let's define the concept of terminal point on this circle as follows: given t e R, starting at the point (r,0), travel a distance of t counterclockwise on the circle if t > 0, or a distance of || clockwise if t