What is the ##sin^(-1)(sqrt(3)/2)##?

##sin^(-1)(sqrt(3)/2) = pi/3## (radians)

##sin^(-1)(sqrt(3)/2) = theta## ##color(white)("XX")##means ##sin(theta)=sqrt(3)/2## ##color(white)("XXXX")##with the restriction that ##theta in [-pi/2,pi/2]##

The possible triangles with this ratio of ##y## to ##"hypotenuse"## (i.e. ##sin##) are pictured below: ...but note that only ##pi/3## falls within the restricted range for ##sin^(-1)##