Integrand size = 22, antiderivative size = 56 \[ \int \frac {x^3}{a x^2+b x^3+c x^4} \, dx=\frac {b \text {arctanh}\left (\frac {b+2 c x}{\sqrt {b^2-4 a c}}\right )}{c \sqrt {b^2-4 a c}}+\frac {\log \left (a+b x+c x^2\right )}{2 c} \]
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Time = 0.03 (sec) , antiderivative size = 56, normalized size of antiderivative = 1.00, number of steps used = 5, number of rules used = 5, \(\frac {\text {number of rules}}{\text {integrand size}}\) = 0.227, Rules used = {1599, 648, 632, 212, 642} \[ \int \frac {x^3}{a x^2+b x^3+c x^4} \, dx=\frac {b \text {arctanh}\left (\frac {b+2 c x}{\sqrt {b^2-4 a c}}\right )}{c \sqrt {b^2-4 a c}}+\frac {\log \left (a+b x+c x^2\right )}{2 c} \]
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Rule 212
Rule 632
Rule 642
Rule 648
Rule 1599
Rubi steps \begin{align*} \text {integral}& = \int \frac {x}{a+b x+c x^2} \, dx \\ & = \frac {\int \frac {b+2 c x}{a+b x+c x^2} \, dx}{2 c}-\frac {b \int \frac {1}{a+b x+c x^2} \, dx}{2 c} \\ & = \frac {\log \left (a+b x+c x^2\right )}{2 c}+\frac {b \text {Subst}\left (\int \frac {1}{b^2-4 a c-x^2} \, dx,x,b+2 c x\right )}{c} \\ & = \frac {b \tanh ^{-1}\left (\frac {b+2 c x}{\sqrt {b^2-4 a c}}\right )}{c \sqrt {b^2-4 a c}}+\frac {\log \left (a+b x+c x^2\right )}{2 c} \\ \end{align*}
Time = 0.02 (sec) , antiderivative size = 57, normalized size of antiderivative = 1.02 \[ \int \frac {x^3}{a x^2+b x^3+c x^4} \, dx=\frac {-\frac {2 b \arctan \left (\frac {b+2 c x}{\sqrt {-b^2+4 a c}}\right )}{\sqrt {-b^2+4 a c}}+\log (a+x (b+c x))}{2 c} \]
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Time = 0.05 (sec) , antiderivative size = 56, normalized size of antiderivative = 1.00
method | result | size |
default | \(\frac {\ln \left (c \,x^{2}+b x +a \right )}{2 c}-\frac {b \arctan \left (\frac {2 c x +b}{\sqrt {4 a c -b^{2}}}\right )}{c \sqrt {4 a c -b^{2}}}\) | \(56\) |
risch | \(\frac {2 \ln \left (-2 \sqrt {-b^{2} \left (4 a c -b^{2}\right )}\, c x -4 a b c +b^{3}-\sqrt {-b^{2} \left (4 a c -b^{2}\right )}\, b \right ) a}{4 a c -b^{2}}-\frac {\ln \left (-2 \sqrt {-b^{2} \left (4 a c -b^{2}\right )}\, c x -4 a b c +b^{3}-\sqrt {-b^{2} \left (4 a c -b^{2}\right )}\, b \right ) b^{2}}{2 c \left (4 a c -b^{2}\right )}+\frac {\ln \left (-2 \sqrt {-b^{2} \left (4 a c -b^{2}\right )}\, c x -4 a b c +b^{3}-\sqrt {-b^{2} \left (4 a c -b^{2}\right )}\, b \right ) \sqrt {-b^{2} \left (4 a c -b^{2}\right )}}{2 c \left (4 a c -b^{2}\right )}+\frac {2 \ln \left (2 \sqrt {-b^{2} \left (4 a c -b^{2}\right )}\, c x -4 a b c +b^{3}+\sqrt {-b^{2} \left (4 a c -b^{2}\right )}\, b \right ) a}{4 a c -b^{2}}-\frac {\ln \left (2 \sqrt {-b^{2} \left (4 a c -b^{2}\right )}\, c x -4 a b c +b^{3}+\sqrt {-b^{2} \left (4 a c -b^{2}\right )}\, b \right ) b^{2}}{2 c \left (4 a c -b^{2}\right )}-\frac {\ln \left (2 \sqrt {-b^{2} \left (4 a c -b^{2}\right )}\, c x -4 a b c +b^{3}+\sqrt {-b^{2} \left (4 a c -b^{2}\right )}\, b \right ) \sqrt {-b^{2} \left (4 a c -b^{2}\right )}}{2 c \left (4 a c -b^{2}\right )}\) | \(443\) |
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none
Time = 0.25 (sec) , antiderivative size = 185, normalized size of antiderivative = 3.30 \[ \int \frac {x^3}{a x^2+b x^3+c x^4} \, dx=\left [\frac {\sqrt {b^{2} - 4 \, a c} b \log \left (\frac {2 \, c^{2} x^{2} + 2 \, b c x + b^{2} - 2 \, a c + \sqrt {b^{2} - 4 \, a c} {\left (2 \, c x + b\right )}}{c x^{2} + b x + a}\right ) + {\left (b^{2} - 4 \, a c\right )} \log \left (c x^{2} + b x + a\right )}{2 \, {\left (b^{2} c - 4 \, a c^{2}\right )}}, \frac {2 \, \sqrt {-b^{2} + 4 \, a c} b \arctan \left (-\frac {\sqrt {-b^{2} + 4 \, a c} {\left (2 \, c x + b\right )}}{b^{2} - 4 \, a c}\right ) + {\left (b^{2} - 4 \, a c\right )} \log \left (c x^{2} + b x + a\right )}{2 \, {\left (b^{2} c - 4 \, a c^{2}\right )}}\right ] \]
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Leaf count of result is larger than twice the leaf count of optimal. 216 vs. \(2 (49) = 98\).
Time = 0.18 (sec) , antiderivative size = 216, normalized size of antiderivative = 3.86 \[ \int \frac {x^3}{a x^2+b x^3+c x^4} \, dx=\left (- \frac {b \sqrt {- 4 a c + b^{2}}}{2 c \left (4 a c - b^{2}\right )} + \frac {1}{2 c}\right ) \log {\left (x + \frac {- 4 a c \left (- \frac {b \sqrt {- 4 a c + b^{2}}}{2 c \left (4 a c - b^{2}\right )} + \frac {1}{2 c}\right ) + 2 a + b^{2} \left (- \frac {b \sqrt {- 4 a c + b^{2}}}{2 c \left (4 a c - b^{2}\right )} + \frac {1}{2 c}\right )}{b} \right )} + \left (\frac {b \sqrt {- 4 a c + b^{2}}}{2 c \left (4 a c - b^{2}\right )} + \frac {1}{2 c}\right ) \log {\left (x + \frac {- 4 a c \left (\frac {b \sqrt {- 4 a c + b^{2}}}{2 c \left (4 a c - b^{2}\right )} + \frac {1}{2 c}\right ) + 2 a + b^{2} \left (\frac {b \sqrt {- 4 a c + b^{2}}}{2 c \left (4 a c - b^{2}\right )} + \frac {1}{2 c}\right )}{b} \right )} \]
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Exception generated. \[ \int \frac {x^3}{a x^2+b x^3+c x^4} \, dx=\text {Exception raised: ValueError} \]
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Time = 0.31 (sec) , antiderivative size = 55, normalized size of antiderivative = 0.98 \[ \int \frac {x^3}{a x^2+b x^3+c x^4} \, dx=-\frac {b \arctan \left (\frac {2 \, c x + b}{\sqrt {-b^{2} + 4 \, a c}}\right )}{\sqrt {-b^{2} + 4 \, a c} c} + \frac {\log \left (c x^{2} + b x + a\right )}{2 \, c} \]
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Time = 0.07 (sec) , antiderivative size = 112, normalized size of antiderivative = 2.00 \[ \int \frac {x^3}{a x^2+b x^3+c x^4} \, dx=\frac {2\,a\,c\,\ln \left (c\,x^2+b\,x+a\right )}{4\,a\,c^2-b^2\,c}-\frac {b\,\mathrm {atan}\left (\frac {b}{\sqrt {4\,a\,c-b^2}}+\frac {2\,c\,x}{\sqrt {4\,a\,c-b^2}}\right )}{c\,\sqrt {4\,a\,c-b^2}}-\frac {b^2\,\ln \left (c\,x^2+b\,x+a\right )}{2\,\left (4\,a\,c^2-b^2\,c\right )} \]
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