JEE Math Practice Question

If $$\cos x{{dy} \over {dx}} - y\sin x = 6x$$, (0 < x < $${\pi \over 2}$$) and $$y\left( {{\pi \over 3}} \right)$$ = 0 then $$y\left( {{\pi \over 6}} \right)$$ is equal to :-

1. A.$$ - {{{\pi ^2}} \over {2 }}$$
2. B.$$ - {{{\pi ^2}} \over {4\sqrt 3 }}$$
3. C.$$ {{{\pi ^2}} \over {2\sqrt 3 }}$$
4. D.$$ - {{{\pi ^2}} \over {2\sqrt 3 }}$$