Question 169069
Note: 660 degrees is a coterminal angle to -60 degrees



{{{csc(660)=1/sin(660)=1/sin(-60)=1/(-sin(60))=-1/sin(60)=-1/(sqrt(3)/2)=-2/sqrt(3)=(-2*sqrt(3))/3}}}



So {{{csc(660)=(-2*sqrt(3))/3}}}