Question

3 -Os valores que faltam para completar a tabela são: *
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Answer 1

$\boxed{f(x)=\cos{2x}}$

$x=\dfrac{\pi}{2}\ \to\ f\bigg(\dfrac{\pi}{2}\bigg)=\cos{\bigg(2\dfrac{\pi}{2}\bigg)}=\cos{\pi}\ \to\ \boxed{f\bigg(\dfrac{\pi}{2}\bigg)=-1}$

$x=2\pi\ \to\ f(2\pi)=\cos{(2(2\pi))}=\cos{4\pi}\ \to\ \boxed{f(2\pi)=1}$

Letra A.