You can put this solution on YOUR website! sin^2 x-3cosx=3
..
sin^2x-3cosx=3
1-cosx^2-3cosx-3=0
1-cosx^2-3cosx)-3=0
-cosx^2-3cosx-2=0
cos^2x+3cosx+2=0
factor
(cosx+2)(cosx+1)=0
cosx+2=0
cosx=-2 (reject, -1=
cosx+1=0
cosx=-1
ans: x=180deg (0< x <360deg)