Question 522880
Using a double-angle or half-angle formula to simplify the given expressions. 
a) IF cos^2(22 degrees)-sin^2(22 degrees)=cos(A degrees), then
using identity: cos 2s=cos^2s-sin^2s
cos^2(22 degrees)-sin^2(22 degrees)=cos 44º 
A= 44º
b) IF cos^2(2x)-sin^2(2x)=cos(B), then
Using same identity:
cos^2(2x)-sin^2(2x)=cos 4x
B=4x