Hint in integration $\int\frac{x^{2}}{\left(x\cos x-\sin x \right )\left( x\sin x+\cos x \right )}\,\mathrm{d}x$ In the following integration 
$$\int \frac{x^{2}}{\left ( x\cos x-\sin x \right )\left ( x\sin x+\cos x \right )}\, \mathrm{d}x$$
I tried alot. But does not get any proper start.
Can anybody provide me a hint.

Notice
$$x^{2}=x^2\left ( \sin^2x+\cos^2x \right )$$
then
\begin{align*}
\int \frac{x^{2}}{\left ( x\cos x-\sin x \right )\left ( x\sin x+\cos x \right )}\, \mathrm{d}x&=\int \frac{x^2\left ( \sin^2x+\cos^2x \right )}{\left ( x\cos x-\sin x \right )\left ( x\sin x+\cos x \right )}\, \mathrm{d}x\\
&=\int \frac{x\cos x}{x\sin x+\cos x}\, \mathrm{d}x+\int \frac{x\sin x}{x\cos x-\sin x}\, \mathrm{d}x\\
&=\ln\left | x\sin x+\cos x \right |-\ln\left | x\cos x-\sin x \right |+C
\end{align*}
