Evaluate the indefinite integral ∫3xx2+1dx\int \frac{3x}{x^2+1} dx∫x2+13xdx.
32arctan(x)+C\frac{3}{2} \arctan(x) + C23arctan(x)+C
ln(x2+1)+C\ln(x^2+1) + Cln(x2+1)+C
3ln(x2+1)+C3 \ln(x^2+1) + C3ln(x2+1)+C
32ln(x2+1)+C\frac{3}{2} \ln(x^2+1) + C23ln(x2+1)+C