Let and . Which one of the following relations is…

MATHEMATICS · Single correct · AP · AP Precalculus · Trigonometric and Polar Functions · Trigonometric and Polar Functions

Problem

Let

a=\cos\left(\dfrac{973\pi}{5}\right)

and

b=\cos\left(-\dfrac{2\pi}{5}\right)

. Which one of the following relations is true? (a)

a>b

(b)

a<b

(c)

a=b

(d) No definite relation between

a

and

b