f ( θ ) = sin ( θ ) {\displaystyle f(\theta )=\sin(\theta )} g ( θ ) = cos ( θ ) {\displaystyle g(\theta )=\cos {(\theta )}} θ = 60 ∘ {\displaystyle \theta =60^{\circ }}
g ( θ 2 ) = g ( 60 ∘ 2 ) = g ( 30 ∘ ) = cos ( 30 ∘ ) = 3 2 {\displaystyle g\left({\frac {\theta }{2}}\right)=g\left({\frac {60^{\circ }}{2}}\right)=g(30^{\circ })=\cos(30^{\circ })={\frac {\sqrt {3}}{2}}}
