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/2pi/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)##