arcsin:[-1,1]→[-π/2,π/2] : arccos:[-1,1]→[0.π]
1)arcsin2x=-1/2 =>2x=-Ï€/6 =>x=-Ï€/12
2) arcsin1/2=Ï€/6 ecuatia devine
Ï€/6+arccosx=Ï€/2
arccosx=Ï€/2-Ï€/6
arccosx=Ï€/3 =>x=1/2
3)1/√2 =√2/2 Ecuatia devine
arcsinx+arccos√2/2=π/2 =>
arcsinx+Ï€/4=Ï€/2
arcsinx=Ï€/2-Ï€/4=Ï€/4