Integration Techniques (Trigo By Parts)

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Could I please get some help on this integration question? My attempts are attached and I would like to know if it is correct. I also think my attempt is rather complicated and would like to know if there is another way to solve the question. Thank you.

Find the antiderivative :

$$\int {(1+\cot \space x)^2 \csc \space x \space dx}$$

*Correction: It should be substitute (ii) into (i) instead of (iii) into (ii)

My Attempt

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$$\int(1+\cot x)^2\csc x\ dx$$

$$=\int\csc\ dx+2\int\csc\cot x\ dx+\int\cot^2x\csc x\ dx$$

The first two are elementary.

$$\int\cot^2x\csc x\ dx=\int\dfrac{\cos^2x}{\sin^3x}\ dx=\int\dfrac{\cos^2x}{\sin^4x}\sin x dx$$

Set $\cos x=u$

Alternatively integrating by parts,

$$\int\cot^2x\csc x\ dx=\int \cos x\dfrac{\cos x}{\sin^3x}\ dx$$

$$=\cos x\int\dfrac{\cos x}{\sin^3x}\ dx-\int\left(\dfrac{d(\cos x)}{dx}\int\dfrac{\cos x}{\sin^3x}\ dx\right)dx$$

$$=-\dfrac{\cos x}{\sin^2x}-\int\dfrac{\sin x}{\sin^2x}\ dx=?$$