Question

the value of cos 22.5 degree is

Answer 1

Since 22.5 is half of 45, I'll use the half-angle identity for cosine:


Since 22.5° is in the first quadrant, then the cosine value is positive, so I'll take the positive root for my answer:
$\frac{ \sqrt{2 + \sqrt{2} } }{2}$
or 0.9238

Answer 2

Answer:

√√2+1/√2√2

Explanation: