Integration by Trig Substitution $u=a \tan(\theta)$ I am currently working on a problem that deals with trig sub to integrate. The worksheet that I have gotten it off of says to reduce it into sine and cosine functions and use the Table of Integrals given:

Here is my work that I have done so far:

From here on out I do not know what to do. It looks nothing like anything in the table of integrals given so I do not know how to move foward!
Thanks in advance for your help!!

With $x=\sin\theta$ this integral is $\frac{1}{81}\int\frac{1-x^2}{x^2}dx$. You can do the rest.
