Question

Evaluate the integral x / (x^2 + 9) dx

Answer 1

\[\int\limits_{}^{} \frac{ x }{ x^2 + 9 } dx\]

Answer 2

use the substitution
\[ \large u=x^2+9\qquad\qquad du=2x\,dx\quad\text{or}\quad
\frac{du}{2}=x\,dx \]