6.2 Trigonometric Functions: Unit Circle Approach/109

$f(x)=\sin(x)$
$g(x)=\cos(x)$
$h(x)=2x$
$p(x)={\frac {x}{2}}$

$(f\cdot g)({\frac {3\pi }{4}})=f(g({\frac {3\pi }{4}})=f\left(-{\frac {\sqrt {2}}{2}}\right)=-{\frac {1}{2}}$