Вам следует запомнить их
1) arccos√2/2 =π/4
2)arccos(-1/2)=2π/3
3)1/2arccos √3/2+1/3arccos(-√2/2)=1/2× π/6+1/3× 3π/4=π/12+π/4=3π+π / 12=4π/12=π/3
4)0,7 arcsin 0 +arcsin(-1/2)= 0,7 ×0 - π/3=-π/3
5)1/2 arcsin (-√3/2)+ arccos(-√3/2)=1/2 × (-π/3)+2π/6=-π/6+2π/6=π/6
6)arctg(-arccos(-√2/2)/arcsin1/2=acrtg(-(π-π/4))/π/6=arctg(-3π/4)/π/6=