6.2 Trigonometric Functions: Unit Circle Approach/101

$f(\theta )=\sin(\theta )$

$\theta =60^{\circ }$

$f(2\theta )$

$f(2\theta )=f(2\cdot 60^{\circ })=f(120^{\circ })=\sin(120^{\circ })={\frac {\sqrt {3}}{2}}$