1.
If y(x)=sinxcosxsinx+cosx+1272827111y(x)=\begin{vmatrix} \sin x & \cos x & \sin x+\cos x+1 \\ 27 & 28 & 27 \\ 1 & 1 & 1 \end{vmatrix}, xRx\in\mathbb{R}, then d2ydx2+y\frac{d^{2}y}{dx^{2}}+y is equal to: