In the unit circle in figure 1, point A(x, y) lies on the circumference of the circle. The radius joining this point to the circle’s center makes an angle, θ, with the positive x-axis. Based on this information and the figure, answer the questions that follow.

Part A
Is there any other point on the circumference of the circle that shares the x-coordinate of point A(x, y)? If so, what are the coordinates of that point?

What is the measure of the angle made by the radius joining this point? Write your answer in radians, and explain how you got the answer. Refer to figure 1 to answer this question.

How do the values of cos theta and cos(2pi - theta) compare? Why?