3. Apresentando o passo a passo, calcule as integrais indefinidas abaixo.
$$
\begin{gathered}
\text { a) }(2,0 \text { ptos }) \int \frac{\mathrm{e}^{\left(\frac{1}{x^{2}}\right)}}{x^{5}} d x \quad \text { b) }(2,0 \text { ptos }) \int \frac{\sin [\ln (x)]}{\tan [\ln (x)]} d x \\
\text { c) }(2,0 \text { ptos }) \int x^{2} \sqrt{x+1} d x
\end{gathered}
$$