\[ \int \frac {x^3 \left (c+d x+e x^2+f x^3\right )}{a+b x^4} \, dx \]
Optimal antiderivative \[ \frac {d x}{b}+\frac {e \,x^{2}}{2 b}+\frac {f \,x^{3}}{3 b}+\frac {c \ln \left (b \,x^{4}+a \right )}{4 b}-\frac {e \arctan \left (\frac {x^{2} \sqrt {b}}{\sqrt {a}}\right ) \sqrt {a}}{2 b^{\frac {3}{2}}}+\frac {a^{\frac {1}{4}} \ln \left (-a^{\frac {1}{4}} b^{\frac {1}{4}} x \sqrt {2}+\sqrt {a}+x^{2} \sqrt {b}\right ) \left (-f \sqrt {a}+d \sqrt {b}\right ) \sqrt {2}}{8 b^{\frac {7}{4}}}-\frac {a^{\frac {1}{4}} \ln \left (a^{\frac {1}{4}} b^{\frac {1}{4}} x \sqrt {2}+\sqrt {a}+x^{2} \sqrt {b}\right ) \left (-f \sqrt {a}+d \sqrt {b}\right ) \sqrt {2}}{8 b^{\frac {7}{4}}}-\frac {a^{\frac {1}{4}} \arctan \left (-1+\frac {b^{\frac {1}{4}} x \sqrt {2}}{a^{\frac {1}{4}}}\right ) \left (f \sqrt {a}+d \sqrt {b}\right ) \sqrt {2}}{4 b^{\frac {7}{4}}}-\frac {a^{\frac {1}{4}} \arctan \left (1+\frac {b^{\frac {1}{4}} x \sqrt {2}}{a^{\frac {1}{4}}}\right ) \left (f \sqrt {a}+d \sqrt {b}\right ) \sqrt {2}}{4 b^{\frac {7}{4}}} \]
command
integrate(x^3*(f*x^3+e*x^2+d*x+c)/(b*x^4+a),x, algorithm="fricas")
Fricas 1.3.8 (sbcl 2.2.11.debian) via sagemath 9.6 output
\[ \text {output too large to display} \]
Fricas 1.3.7 via sagemath 9.3 output \[ \text {Timed out} \]