Question

a) cos(arcsin√3/2)
в) cos(arctg(-√3/3))

Answer 1

$1)Cos(arcSin\frac{\sqrt{3}}{2})=Cos\frac{\pi }{3}=\frac{1}{2}\\\\Otvet:\boxed{\frac{1}{2}} \\\\2)Cos(arctg(-\frac{\sqrt{3}}{3})= Cos(-\frac{\pi }{6})=Cos\frac{\pi }{6}=\frac{\sqrt{3} }{2}\\\\Otvet:\boxed{\frac{\sqrt{3}}{2}}$