Question

os valores de sen 150°, sen 315°, cos 60° e cos 240°são respectivamente

Answer 1

'$\Large\boxed{\begin{array}{l}\sf sen (150^\circ)=sen(180^\circ-150^\circ)=sen(30^\circ)=\dfrac{1}{2}\\\\\sf sen(315^\circ)=-sen(360-315^\circ)=-sen(45^\circ)=-\dfrac{\sqrt{2}}{2}\\\\\sf cos(60^\circ)=\dfrac{1}{2}\\\\\sf cos(240^\circ)=-cos(240^\circ-180^\circ)=-cos(60^\circ)=-\dfrac{1}{2}\end{array}}$