\[ \int \sqrt{x^2+3 x} d x= \]
\(\sqrt{x^{2}+3x}+\mathrm{log}\sqrt{x^{2}+3x}+c\), where c is the constant of integration.
\(\frac{2x+3}{4}\sqrt{x^{2}+3x}-\frac{9}{8}\mathrm{log}(x+\sqrt{x^{2}+3x})+c\), where c is the constant of integration.
\(x\sqrt{x^{2}+3x}+\mathrm{log}(x+\sqrt{x^{2}+3x})+\mathrm{c}\), where c is the constant of integration.
\(x+3\sqrt{x^{2}+3x}+\frac{3}{2}\mathrm{log}(x+\sqrt{x^{2}+3x})+\mathrm{c}\), where c is the constant of integration.