3.895 \(\int \frac{1}{a-b x^2+c x^4} \, dx\)

Optimal. Leaf size=150 \[ \frac{\sqrt{2} \sqrt{c} \tanh ^{-1}\left (\frac{\sqrt{2} \sqrt{c} x}{\sqrt{b-\sqrt{b^2-4 a c}}}\right )}{\sqrt{b^2-4 a c} \sqrt{b-\sqrt{b^2-4 a c}}}-\frac{\sqrt{2} \sqrt{c} \tanh ^{-1}\left (\frac{\sqrt{2} \sqrt{c} x}{\sqrt{\sqrt{b^2-4 a c}+b}}\right )}{\sqrt{b^2-4 a c} \sqrt{\sqrt{b^2-4 a c}+b}} \]

[Out]

(Sqrt[2]*Sqrt[c]*ArcTanh[(Sqrt[2]*Sqrt[c]*x)/Sqrt[b - Sqrt[b^2 - 4*a*c]]])/(Sqrt[b^2 - 4*a*c]*Sqrt[b - Sqrt[b^
2 - 4*a*c]]) - (Sqrt[2]*Sqrt[c]*ArcTanh[(Sqrt[2]*Sqrt[c]*x)/Sqrt[b + Sqrt[b^2 - 4*a*c]]])/(Sqrt[b^2 - 4*a*c]*S
qrt[b + Sqrt[b^2 - 4*a*c]])

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Rubi [A]  time = 0.0724572, antiderivative size = 150, normalized size of antiderivative = 1., number of steps used = 3, number of rules used = 2, integrand size = 15, \(\frac{\text{number of rules}}{\text{integrand size}}\) = 0.133, Rules used = {1093, 208} \[ \frac{\sqrt{2} \sqrt{c} \tanh ^{-1}\left (\frac{\sqrt{2} \sqrt{c} x}{\sqrt{b-\sqrt{b^2-4 a c}}}\right )}{\sqrt{b^2-4 a c} \sqrt{b-\sqrt{b^2-4 a c}}}-\frac{\sqrt{2} \sqrt{c} \tanh ^{-1}\left (\frac{\sqrt{2} \sqrt{c} x}{\sqrt{\sqrt{b^2-4 a c}+b}}\right )}{\sqrt{b^2-4 a c} \sqrt{\sqrt{b^2-4 a c}+b}} \]

Antiderivative was successfully verified.

[In]

Int[(a - b*x^2 + c*x^4)^(-1),x]

[Out]

(Sqrt[2]*Sqrt[c]*ArcTanh[(Sqrt[2]*Sqrt[c]*x)/Sqrt[b - Sqrt[b^2 - 4*a*c]]])/(Sqrt[b^2 - 4*a*c]*Sqrt[b - Sqrt[b^
2 - 4*a*c]]) - (Sqrt[2]*Sqrt[c]*ArcTanh[(Sqrt[2]*Sqrt[c]*x)/Sqrt[b + Sqrt[b^2 - 4*a*c]]])/(Sqrt[b^2 - 4*a*c]*S
qrt[b + Sqrt[b^2 - 4*a*c]])

Rule 1093

Int[((a_) + (b_.)*(x_)^2 + (c_.)*(x_)^4)^(-1), x_Symbol] :> With[{q = Rt[b^2 - 4*a*c, 2]}, Dist[c/q, Int[1/(b/
2 - q/2 + c*x^2), x], x] - Dist[c/q, Int[1/(b/2 + q/2 + c*x^2), x], x]] /; FreeQ[{a, b, c}, x] && NeQ[b^2 - 4*
a*c, 0] && PosQ[b^2 - 4*a*c]

Rule 208

Int[((a_) + (b_.)*(x_)^2)^(-1), x_Symbol] :> Simp[(Rt[-(a/b), 2]*ArcTanh[x/Rt[-(a/b), 2]])/a, x] /; FreeQ[{a,
b}, x] && NegQ[a/b]

Rubi steps

\begin{align*} \int \frac{1}{a-b x^2+c x^4} \, dx &=\frac{c \int \frac{1}{-\frac{b}{2}-\frac{1}{2} \sqrt{b^2-4 a c}+c x^2} \, dx}{\sqrt{b^2-4 a c}}-\frac{c \int \frac{1}{-\frac{b}{2}+\frac{1}{2} \sqrt{b^2-4 a c}+c x^2} \, dx}{\sqrt{b^2-4 a c}}\\ &=\frac{\sqrt{2} \sqrt{c} \tanh ^{-1}\left (\frac{\sqrt{2} \sqrt{c} x}{\sqrt{b-\sqrt{b^2-4 a c}}}\right )}{\sqrt{b^2-4 a c} \sqrt{b-\sqrt{b^2-4 a c}}}-\frac{\sqrt{2} \sqrt{c} \tanh ^{-1}\left (\frac{\sqrt{2} \sqrt{c} x}{\sqrt{b+\sqrt{b^2-4 a c}}}\right )}{\sqrt{b^2-4 a c} \sqrt{b+\sqrt{b^2-4 a c}}}\\ \end{align*}

Mathematica [A]  time = 0.0839519, size = 137, normalized size = 0.91 \[ \frac{\sqrt{2} \sqrt{c} \left (\frac{\tan ^{-1}\left (\frac{\sqrt{2} \sqrt{c} x}{\sqrt{-\sqrt{b^2-4 a c}-b}}\right )}{\sqrt{-\sqrt{b^2-4 a c}-b}}-\frac{\tan ^{-1}\left (\frac{\sqrt{2} \sqrt{c} x}{\sqrt{\sqrt{b^2-4 a c}-b}}\right )}{\sqrt{\sqrt{b^2-4 a c}-b}}\right )}{\sqrt{b^2-4 a c}} \]

Antiderivative was successfully verified.

[In]

Integrate[(a - b*x^2 + c*x^4)^(-1),x]

[Out]

(Sqrt[2]*Sqrt[c]*(ArcTan[(Sqrt[2]*Sqrt[c]*x)/Sqrt[-b - Sqrt[b^2 - 4*a*c]]]/Sqrt[-b - Sqrt[b^2 - 4*a*c]] - ArcT
an[(Sqrt[2]*Sqrt[c]*x)/Sqrt[-b + Sqrt[b^2 - 4*a*c]]]/Sqrt[-b + Sqrt[b^2 - 4*a*c]]))/Sqrt[b^2 - 4*a*c]

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Maple [A]  time = 0.172, size = 116, normalized size = 0.8 \begin{align*} -{c\sqrt{2}\arctan \left ({cx\sqrt{2}{\frac{1}{\sqrt{ \left ( -b+\sqrt{-4\,ac+{b}^{2}} \right ) c}}}} \right ){\frac{1}{\sqrt{-4\,ac+{b}^{2}}}}{\frac{1}{\sqrt{ \left ( -b+\sqrt{-4\,ac+{b}^{2}} \right ) c}}}}-{c\sqrt{2}{\it Artanh} \left ({cx\sqrt{2}{\frac{1}{\sqrt{ \left ( b+\sqrt{-4\,ac+{b}^{2}} \right ) c}}}} \right ){\frac{1}{\sqrt{-4\,ac+{b}^{2}}}}{\frac{1}{\sqrt{ \left ( b+\sqrt{-4\,ac+{b}^{2}} \right ) c}}}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

int(1/(c*x^4-b*x^2+a),x)

[Out]

-c/(-4*a*c+b^2)^(1/2)*2^(1/2)/((-b+(-4*a*c+b^2)^(1/2))*c)^(1/2)*arctan(x*c*2^(1/2)/((-b+(-4*a*c+b^2)^(1/2))*c)
^(1/2))-c/(-4*a*c+b^2)^(1/2)*2^(1/2)/((b+(-4*a*c+b^2)^(1/2))*c)^(1/2)*arctanh(x*c*2^(1/2)/((b+(-4*a*c+b^2)^(1/
2))*c)^(1/2))

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Maxima [F]  time = 0., size = 0, normalized size = 0. \begin{align*} \int \frac{1}{c x^{4} - b x^{2} + a}\,{d x} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(c*x^4-b*x^2+a),x, algorithm="maxima")

[Out]

integrate(1/(c*x^4 - b*x^2 + a), x)

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Fricas [B]  time = 1.58474, size = 1312, normalized size = 8.75 \begin{align*} -\frac{1}{2} \, \sqrt{\frac{1}{2}} \sqrt{\frac{b + \frac{a b^{2} - 4 \, a^{2} c}{\sqrt{a^{2} b^{2} - 4 \, a^{3} c}}}{a b^{2} - 4 \, a^{2} c}} \log \left (2 \, c x + \sqrt{\frac{1}{2}}{\left (b^{2} - 4 \, a c - \frac{a b^{3} - 4 \, a^{2} b c}{\sqrt{a^{2} b^{2} - 4 \, a^{3} c}}\right )} \sqrt{\frac{b + \frac{a b^{2} - 4 \, a^{2} c}{\sqrt{a^{2} b^{2} - 4 \, a^{3} c}}}{a b^{2} - 4 \, a^{2} c}}\right ) + \frac{1}{2} \, \sqrt{\frac{1}{2}} \sqrt{\frac{b + \frac{a b^{2} - 4 \, a^{2} c}{\sqrt{a^{2} b^{2} - 4 \, a^{3} c}}}{a b^{2} - 4 \, a^{2} c}} \log \left (2 \, c x - \sqrt{\frac{1}{2}}{\left (b^{2} - 4 \, a c - \frac{a b^{3} - 4 \, a^{2} b c}{\sqrt{a^{2} b^{2} - 4 \, a^{3} c}}\right )} \sqrt{\frac{b + \frac{a b^{2} - 4 \, a^{2} c}{\sqrt{a^{2} b^{2} - 4 \, a^{3} c}}}{a b^{2} - 4 \, a^{2} c}}\right ) - \frac{1}{2} \, \sqrt{\frac{1}{2}} \sqrt{\frac{b - \frac{a b^{2} - 4 \, a^{2} c}{\sqrt{a^{2} b^{2} - 4 \, a^{3} c}}}{a b^{2} - 4 \, a^{2} c}} \log \left (2 \, c x + \sqrt{\frac{1}{2}}{\left (b^{2} - 4 \, a c + \frac{a b^{3} - 4 \, a^{2} b c}{\sqrt{a^{2} b^{2} - 4 \, a^{3} c}}\right )} \sqrt{\frac{b - \frac{a b^{2} - 4 \, a^{2} c}{\sqrt{a^{2} b^{2} - 4 \, a^{3} c}}}{a b^{2} - 4 \, a^{2} c}}\right ) + \frac{1}{2} \, \sqrt{\frac{1}{2}} \sqrt{\frac{b - \frac{a b^{2} - 4 \, a^{2} c}{\sqrt{a^{2} b^{2} - 4 \, a^{3} c}}}{a b^{2} - 4 \, a^{2} c}} \log \left (2 \, c x - \sqrt{\frac{1}{2}}{\left (b^{2} - 4 \, a c + \frac{a b^{3} - 4 \, a^{2} b c}{\sqrt{a^{2} b^{2} - 4 \, a^{3} c}}\right )} \sqrt{\frac{b - \frac{a b^{2} - 4 \, a^{2} c}{\sqrt{a^{2} b^{2} - 4 \, a^{3} c}}}{a b^{2} - 4 \, a^{2} c}}\right ) \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(c*x^4-b*x^2+a),x, algorithm="fricas")

[Out]

-1/2*sqrt(1/2)*sqrt((b + (a*b^2 - 4*a^2*c)/sqrt(a^2*b^2 - 4*a^3*c))/(a*b^2 - 4*a^2*c))*log(2*c*x + sqrt(1/2)*(
b^2 - 4*a*c - (a*b^3 - 4*a^2*b*c)/sqrt(a^2*b^2 - 4*a^3*c))*sqrt((b + (a*b^2 - 4*a^2*c)/sqrt(a^2*b^2 - 4*a^3*c)
)/(a*b^2 - 4*a^2*c))) + 1/2*sqrt(1/2)*sqrt((b + (a*b^2 - 4*a^2*c)/sqrt(a^2*b^2 - 4*a^3*c))/(a*b^2 - 4*a^2*c))*
log(2*c*x - sqrt(1/2)*(b^2 - 4*a*c - (a*b^3 - 4*a^2*b*c)/sqrt(a^2*b^2 - 4*a^3*c))*sqrt((b + (a*b^2 - 4*a^2*c)/
sqrt(a^2*b^2 - 4*a^3*c))/(a*b^2 - 4*a^2*c))) - 1/2*sqrt(1/2)*sqrt((b - (a*b^2 - 4*a^2*c)/sqrt(a^2*b^2 - 4*a^3*
c))/(a*b^2 - 4*a^2*c))*log(2*c*x + sqrt(1/2)*(b^2 - 4*a*c + (a*b^3 - 4*a^2*b*c)/sqrt(a^2*b^2 - 4*a^3*c))*sqrt(
(b - (a*b^2 - 4*a^2*c)/sqrt(a^2*b^2 - 4*a^3*c))/(a*b^2 - 4*a^2*c))) + 1/2*sqrt(1/2)*sqrt((b - (a*b^2 - 4*a^2*c
)/sqrt(a^2*b^2 - 4*a^3*c))/(a*b^2 - 4*a^2*c))*log(2*c*x - sqrt(1/2)*(b^2 - 4*a*c + (a*b^3 - 4*a^2*b*c)/sqrt(a^
2*b^2 - 4*a^3*c))*sqrt((b - (a*b^2 - 4*a^2*c)/sqrt(a^2*b^2 - 4*a^3*c))/(a*b^2 - 4*a^2*c)))

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Sympy [A]  time = 0.943064, size = 87, normalized size = 0.58 \begin{align*} \operatorname{RootSum}{\left (t^{4} \left (256 a^{3} c^{2} - 128 a^{2} b^{2} c + 16 a b^{4}\right ) + t^{2} \left (16 a b c - 4 b^{3}\right ) + c, \left ( t \mapsto t \log{\left (x + \frac{- 32 t^{3} a^{2} b c + 8 t^{3} a b^{3} + 4 t a c - 2 t b^{2}}{c} \right )} \right )\right )} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(c*x**4-b*x**2+a),x)

[Out]

RootSum(_t**4*(256*a**3*c**2 - 128*a**2*b**2*c + 16*a*b**4) + _t**2*(16*a*b*c - 4*b**3) + c, Lambda(_t, _t*log
(x + (-32*_t**3*a**2*b*c + 8*_t**3*a*b**3 + 4*_t*a*c - 2*_t*b**2)/c)))

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Giac [C]  time = 1.56458, size = 1296, normalized size = 8.64 \begin{align*} \text{result too large to display} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(c*x^4-b*x^2+a),x, algorithm="giac")

[Out]

1/2*(((a*c^3)^(1/4)*b^2 - 4*(a*c^3)^(1/4)*a*c - (a*c^3)^(1/4)*sqrt(b^2 - 4*a*c)*b)*cosh(1/2*imag_part(arccos(1
/2*sqrt(a*c)*b/(a*abs(c)))))*sin(1/2*real_part(arccos(1/2*sqrt(a*c)*b/(a*abs(c))))) - ((a*c^3)^(1/4)*b^2 - 4*(
a*c^3)^(1/4)*a*c - (a*c^3)^(1/4)*sqrt(b^2 - 4*a*c)*b)*sin(1/2*real_part(arccos(1/2*sqrt(a*c)*b/(a*abs(c)))))*s
inh(1/2*imag_part(arccos(1/2*sqrt(a*c)*b/(a*abs(c))))))*arctan(((a/c)^(1/4)*cos(1/2*arccos(1/2*sqrt(a*c)*b/(a*
abs(c)))) + x)/((a/c)^(1/4)*sin(1/2*arccos(1/2*sqrt(a*c)*b/(a*abs(c))))))/(a*b^2*c - 4*a^2*c^2) + 1/2*(((a*c^3
)^(1/4)*b^2 - 4*(a*c^3)^(1/4)*a*c - (a*c^3)^(1/4)*sqrt(b^2 - 4*a*c)*b)*cosh(1/2*imag_part(arccos(1/2*sqrt(a*c)
*b/(a*abs(c)))))*sin(1/2*real_part(arccos(1/2*sqrt(a*c)*b/(a*abs(c))))) - ((a*c^3)^(1/4)*b^2 - 4*(a*c^3)^(1/4)
*a*c - (a*c^3)^(1/4)*sqrt(b^2 - 4*a*c)*b)*sin(1/2*real_part(arccos(1/2*sqrt(a*c)*b/(a*abs(c)))))*sinh(1/2*imag
_part(arccos(1/2*sqrt(a*c)*b/(a*abs(c))))))*arctan(-((a/c)^(1/4)*cos(1/2*arccos(1/2*sqrt(a*c)*b/(a*abs(c)))) -
x)/((a/c)^(1/4)*sin(1/2*arccos(1/2*sqrt(a*c)*b/(a*abs(c))))))/(a*b^2*c - 4*a^2*c^2) + 1/4*(((a*c^3)^(1/4)*b^2
- 4*(a*c^3)^(1/4)*a*c - (a*c^3)^(1/4)*sqrt(b^2 - 4*a*c)*b)*cos(1/2*real_part(arccos(1/2*sqrt(a*c)*b/(a*abs(c)
))))*cosh(1/2*imag_part(arccos(1/2*sqrt(a*c)*b/(a*abs(c))))) - ((a*c^3)^(1/4)*b^2 - 4*(a*c^3)^(1/4)*a*c - (a*c
^3)^(1/4)*sqrt(b^2 - 4*a*c)*b)*cos(1/2*real_part(arccos(1/2*sqrt(a*c)*b/(a*abs(c)))))*sinh(1/2*imag_part(arcco
s(1/2*sqrt(a*c)*b/(a*abs(c))))))*log(2*x*(a/c)^(1/4)*cos(1/2*arccos(1/2*sqrt(a*c)*b/(a*abs(c)))) + x^2 + sqrt(
a/c))/(a*b^2*c - 4*a^2*c^2) - 1/4*(((a*c^3)^(1/4)*b^2 - 4*(a*c^3)^(1/4)*a*c - (a*c^3)^(1/4)*sqrt(b^2 - 4*a*c)*
b)*cos(1/2*real_part(arccos(1/2*sqrt(a*c)*b/(a*abs(c)))))*cosh(1/2*imag_part(arccos(1/2*sqrt(a*c)*b/(a*abs(c))
))) - ((a*c^3)^(1/4)*b^2 - 4*(a*c^3)^(1/4)*a*c - (a*c^3)^(1/4)*sqrt(b^2 - 4*a*c)*b)*cos(1/2*real_part(arccos(1
/2*sqrt(a*c)*b/(a*abs(c)))))*sinh(1/2*imag_part(arccos(1/2*sqrt(a*c)*b/(a*abs(c))))))*log(-2*x*(a/c)^(1/4)*cos
(1/2*arccos(1/2*sqrt(a*c)*b/(a*abs(c)))) + x^2 + sqrt(a/c))/(a*b^2*c - 4*a^2*c^2)