Evaluate the indefinite integral
$$\int\frac {\csc^2{x}-2005}{\cos^{2005}{x}} dx$$
I tried multiplying and dividing by $\sec^2 {x} $ and then setting $\tan{x}=y$ but no good. Then I set $\cos {x}=t $ and tried to create $\sin {x} $ in the numerator. But the integral which came was also a difficult one.
Please Help!
Thanks!
P.S. I am a high school student so kindly use elementary methods only. Thanks again!