3 arcsin (1/2) + 4arccos (-1/√2) - arcctg(-√3)

arcsin (1/2)=π/6 arccos (-1/√2)=3π/4 arcctg(-√3)=2π/33 arcsin (1/2) + 4arccos (-1/√2) - arcctg(-√3)=π/2+3π-2π/3=17π/6