Trigonometric sum.

[man111]

Let $-\frac{\pi}{4}\leq x,y\leq\frac{\pi}{4}$ such that for some positive integer $n ,nx^3+sinx-2010=0$ and

$4ny^3+sinx.cosy+1005=0$, then the value of $sin(x+2y)+cos(x+2y)$ is