Respostas AVA

FUNÇÕES COMPLEXAS

O valor da expressão $\displaystyle{\cos{{\left({4}\frac{\pi}{{3}}\right)}}}.{\cos{{\left({5}\frac{\pi}{{6}}\right)}}}+{\cos{{\left(\frac{\pi}{{6}}\right)}}}.{\cos{{\left({5}\frac{\pi}{{3}}\right)}}}$

$\displaystyle\frac{\sqrt{{{3}}}}{{4}}$
$\displaystyle\frac{{1}}{{4}}$
$\displaystyle{3}\frac{\sqrt{{{2}}}}{{2}}$
$\displaystyle\frac{\sqrt{{{3}}}}{{2}}$
$\displaystyle\frac{{1}}{{2}}$