Question

how do i use the half angle formula for a 22.5 degree angle for both cosine and sine

Answer 1

hey liz..hi

see

cos^2 t = (1 + cos(2t))/2

if t = 22.5

cos^2 (22.5) = (1 - cos 45)/2

Answer 2

22.5 = 45/2

Answer 3

The formula is

\[\cos^{2} \theta = (1 + \cos (2\theta))/2\]