\[ \int \left (\frac {b}{x^3}\right )^{2/3} \, dx \]
Optimal antiderivative \[ -\left (\frac {b}{x^{3}}\right )^{\frac {2}{3}} x \]
command
integrate((b/x^3)^(2/3),x, algorithm="giac")
Giac 1.9.0-11 via sagemath 9.6 output
\[ -x \left (\frac {b}{x^{3}}\right )^{\frac {2}{3}} \]
Giac 1.7.0 via sagemath 9.3 output
\[ \int \left (\frac {b}{x^{3}}\right )^{\frac {2}{3}}\,{d x} \]________________________________________________________________________________________