Question

Points A, B, and C are plotted on the unit circle.

Which of the coordinates is equal to cos (pi)

A. x-coordinate of point A

B. y-coordinate of point A

C. x-coordinate of point B

D. y-coordinate of point B

E. x-coordinate of point C

F. y-coordinate of point C

Answer 1

c. x-coordinate of point B

Explanation:

khan

Answer 2

E. x-coordinate of point C

Explanation:

Consider the diagram of the unit circle which has been drawn and attached.

Using a calculator in radians,
`cos (\pi)=-1`

On the unit circle, out of points A, B and C, the point -1 is at point C.

Point C is located at (-1,0).

Therefore,
`cos (\pi)` is the x-coordinate of point C.

The correct option is E.