Question

Знайдіть значення cos (30°)- sin (-60°)

Answer 1

$\star\star\star\\\\\sin(-\alpha)=-\sin\alpha\\\\\sin60^\circ=\cos30^\circ=\dfrac{\sqrt3}{2}\\\\\star\star\star\\\\\\\cos30^\circ-\sin(-60^\circ)=\dfrac{\sqrt3}{2}-\bigg(-\dfrac{\sqrt3}{2}\bigg)=\dfrac{\sqrt3}{2}+\dfrac{\sqrt3}{2}=\boxed{\sqrt3}$