Answer :
It is given that sin^2x-sinx-6=0
and the solution is in the interval [0,2n)
Now the equation is quadratic in nature
Therefore solve the equation to get:
sin^2x-sinx-6=0
sin^2x-3sinx+2sinx-6=0
sinx(sinx-3)+2(sinx-3)=0
(sinx+2)(sinx-3)=0
sinx=-2 or sinx=3
Both are not possible since sinx always belongs to [-1,1]
Hence value of -2 or -3 is not valid
Hence the option is D No solution.