Question

[Trigo]
http://prntscr.com/10g6ie

Answer 1

The thing that comes to my mind is that you have a cos given: ax and a sin given: (ax+sqrt(1-a^2x^2)/sqrt2) and sin^2 + cos^2=1

Answer 2

Someone have a better idea?

Answer 3

its not cos..its cos inverse..arc cos(x)

Answer 4

Yes I understand but in the expression:
\[\cos ^{-1}(1/2)=\frac{\pi}{3}\]
the cosine is 1/2