Question

How do you find the exact value of cos 33pi/4?

Answer 1

`cos((33pi)/4) = sqrt(2)/2`

Explanation:

`(33pi)/4` is equivalent to `(32pi)/4 + pi/4 = 2*(2pi)+pi/4 = pi/4color(white)("XX")`(since `2pi = 0`, a complete circle)

`cos(pi/4) = 1/sqrt(2) = sqrt(2)/2color(white)("XXX")`(this is one of the standard angles)