3.378 \(\int x^4 (a+b x^2)^{3/2} \, dx\)

Optimal. Leaf size=115 \[ -\frac{3 a^3 x \sqrt{a+b x^2}}{128 b^2}+\frac{3 a^4 \tanh ^{-1}\left (\frac{\sqrt{b} x}{\sqrt{a+b x^2}}\right )}{128 b^{5/2}}+\frac{a^2 x^3 \sqrt{a+b x^2}}{64 b}+\frac{1}{8} x^5 \left (a+b x^2\right )^{3/2}+\frac{1}{16} a x^5 \sqrt{a+b x^2} \]

[Out]

(-3*a^3*x*Sqrt[a + b*x^2])/(128*b^2) + (a^2*x^3*Sqrt[a + b*x^2])/(64*b) + (a*x^5*Sqrt[a + b*x^2])/16 + (x^5*(a
 + b*x^2)^(3/2))/8 + (3*a^4*ArcTanh[(Sqrt[b]*x)/Sqrt[a + b*x^2]])/(128*b^(5/2))

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Rubi [A]  time = 0.0423694, antiderivative size = 115, normalized size of antiderivative = 1., number of steps used = 6, number of rules used = 4, integrand size = 15, \(\frac{\text{number of rules}}{\text{integrand size}}\) = 0.267, Rules used = {279, 321, 217, 206} \[ -\frac{3 a^3 x \sqrt{a+b x^2}}{128 b^2}+\frac{3 a^4 \tanh ^{-1}\left (\frac{\sqrt{b} x}{\sqrt{a+b x^2}}\right )}{128 b^{5/2}}+\frac{a^2 x^3 \sqrt{a+b x^2}}{64 b}+\frac{1}{8} x^5 \left (a+b x^2\right )^{3/2}+\frac{1}{16} a x^5 \sqrt{a+b x^2} \]

Antiderivative was successfully verified.

[In]

Int[x^4*(a + b*x^2)^(3/2),x]

[Out]

(-3*a^3*x*Sqrt[a + b*x^2])/(128*b^2) + (a^2*x^3*Sqrt[a + b*x^2])/(64*b) + (a*x^5*Sqrt[a + b*x^2])/16 + (x^5*(a
 + b*x^2)^(3/2))/8 + (3*a^4*ArcTanh[(Sqrt[b]*x)/Sqrt[a + b*x^2]])/(128*b^(5/2))

Rule 279

Int[((c_.)*(x_))^(m_.)*((a_) + (b_.)*(x_)^(n_))^(p_), x_Symbol] :> Simp[((c*x)^(m + 1)*(a + b*x^n)^p)/(c*(m +
n*p + 1)), x] + Dist[(a*n*p)/(m + n*p + 1), Int[(c*x)^m*(a + b*x^n)^(p - 1), x], x] /; FreeQ[{a, b, c, m}, x]
&& IGtQ[n, 0] && GtQ[p, 0] && NeQ[m + n*p + 1, 0] && IntBinomialQ[a, b, c, n, m, p, x]

Rule 321

Int[((c_.)*(x_))^(m_)*((a_) + (b_.)*(x_)^(n_))^(p_), x_Symbol] :> Simp[(c^(n - 1)*(c*x)^(m - n + 1)*(a + b*x^n
)^(p + 1))/(b*(m + n*p + 1)), x] - Dist[(a*c^n*(m - n + 1))/(b*(m + n*p + 1)), Int[(c*x)^(m - n)*(a + b*x^n)^p
, x], x] /; FreeQ[{a, b, c, p}, x] && IGtQ[n, 0] && GtQ[m, n - 1] && NeQ[m + n*p + 1, 0] && IntBinomialQ[a, b,
 c, n, m, p, x]

Rule 217

Int[1/Sqrt[(a_) + (b_.)*(x_)^2], x_Symbol] :> Subst[Int[1/(1 - b*x^2), x], x, x/Sqrt[a + b*x^2]] /; FreeQ[{a,
b}, x] &&  !GtQ[a, 0]

Rule 206

Int[((a_) + (b_.)*(x_)^2)^(-1), x_Symbol] :> Simp[(1*ArcTanh[(Rt[-b, 2]*x)/Rt[a, 2]])/(Rt[a, 2]*Rt[-b, 2]), x]
 /; FreeQ[{a, b}, x] && NegQ[a/b] && (GtQ[a, 0] || LtQ[b, 0])

Rubi steps

\begin{align*} \int x^4 \left (a+b x^2\right )^{3/2} \, dx &=\frac{1}{8} x^5 \left (a+b x^2\right )^{3/2}+\frac{1}{8} (3 a) \int x^4 \sqrt{a+b x^2} \, dx\\ &=\frac{1}{16} a x^5 \sqrt{a+b x^2}+\frac{1}{8} x^5 \left (a+b x^2\right )^{3/2}+\frac{1}{16} a^2 \int \frac{x^4}{\sqrt{a+b x^2}} \, dx\\ &=\frac{a^2 x^3 \sqrt{a+b x^2}}{64 b}+\frac{1}{16} a x^5 \sqrt{a+b x^2}+\frac{1}{8} x^5 \left (a+b x^2\right )^{3/2}-\frac{\left (3 a^3\right ) \int \frac{x^2}{\sqrt{a+b x^2}} \, dx}{64 b}\\ &=-\frac{3 a^3 x \sqrt{a+b x^2}}{128 b^2}+\frac{a^2 x^3 \sqrt{a+b x^2}}{64 b}+\frac{1}{16} a x^5 \sqrt{a+b x^2}+\frac{1}{8} x^5 \left (a+b x^2\right )^{3/2}+\frac{\left (3 a^4\right ) \int \frac{1}{\sqrt{a+b x^2}} \, dx}{128 b^2}\\ &=-\frac{3 a^3 x \sqrt{a+b x^2}}{128 b^2}+\frac{a^2 x^3 \sqrt{a+b x^2}}{64 b}+\frac{1}{16} a x^5 \sqrt{a+b x^2}+\frac{1}{8} x^5 \left (a+b x^2\right )^{3/2}+\frac{\left (3 a^4\right ) \operatorname{Subst}\left (\int \frac{1}{1-b x^2} \, dx,x,\frac{x}{\sqrt{a+b x^2}}\right )}{128 b^2}\\ &=-\frac{3 a^3 x \sqrt{a+b x^2}}{128 b^2}+\frac{a^2 x^3 \sqrt{a+b x^2}}{64 b}+\frac{1}{16} a x^5 \sqrt{a+b x^2}+\frac{1}{8} x^5 \left (a+b x^2\right )^{3/2}+\frac{3 a^4 \tanh ^{-1}\left (\frac{\sqrt{b} x}{\sqrt{a+b x^2}}\right )}{128 b^{5/2}}\\ \end{align*}

Mathematica [A]  time = 0.130364, size = 94, normalized size = 0.82 \[ \frac{\sqrt{a+b x^2} \left (\sqrt{b} x \left (2 a^2 b x^2-3 a^3+24 a b^2 x^4+16 b^3 x^6\right )+\frac{3 a^{7/2} \sinh ^{-1}\left (\frac{\sqrt{b} x}{\sqrt{a}}\right )}{\sqrt{\frac{b x^2}{a}+1}}\right )}{128 b^{5/2}} \]

Antiderivative was successfully verified.

[In]

Integrate[x^4*(a + b*x^2)^(3/2),x]

[Out]

(Sqrt[a + b*x^2]*(Sqrt[b]*x*(-3*a^3 + 2*a^2*b*x^2 + 24*a*b^2*x^4 + 16*b^3*x^6) + (3*a^(7/2)*ArcSinh[(Sqrt[b]*x
)/Sqrt[a]])/Sqrt[1 + (b*x^2)/a]))/(128*b^(5/2))

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Maple [A]  time = 0.006, size = 95, normalized size = 0.8 \begin{align*}{\frac{{x}^{3}}{8\,b} \left ( b{x}^{2}+a \right ) ^{{\frac{5}{2}}}}-{\frac{ax}{16\,{b}^{2}} \left ( b{x}^{2}+a \right ) ^{{\frac{5}{2}}}}+{\frac{{a}^{2}x}{64\,{b}^{2}} \left ( b{x}^{2}+a \right ) ^{{\frac{3}{2}}}}+{\frac{3\,{a}^{3}x}{128\,{b}^{2}}\sqrt{b{x}^{2}+a}}+{\frac{3\,{a}^{4}}{128}\ln \left ( x\sqrt{b}+\sqrt{b{x}^{2}+a} \right ){b}^{-{\frac{5}{2}}}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

int(x^4*(b*x^2+a)^(3/2),x)

[Out]

1/8*x^3*(b*x^2+a)^(5/2)/b-1/16/b^2*a*x*(b*x^2+a)^(5/2)+1/64/b^2*a^2*x*(b*x^2+a)^(3/2)+3/128*a^3*x*(b*x^2+a)^(1
/2)/b^2+3/128/b^(5/2)*a^4*ln(x*b^(1/2)+(b*x^2+a)^(1/2))

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Maxima [F(-2)]  time = 0., size = 0, normalized size = 0. \begin{align*} \text{Exception raised: ValueError} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(x^4*(b*x^2+a)^(3/2),x, algorithm="maxima")

[Out]

Exception raised: ValueError

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Fricas [A]  time = 1.66426, size = 396, normalized size = 3.44 \begin{align*} \left [\frac{3 \, a^{4} \sqrt{b} \log \left (-2 \, b x^{2} - 2 \, \sqrt{b x^{2} + a} \sqrt{b} x - a\right ) + 2 \,{\left (16 \, b^{4} x^{7} + 24 \, a b^{3} x^{5} + 2 \, a^{2} b^{2} x^{3} - 3 \, a^{3} b x\right )} \sqrt{b x^{2} + a}}{256 \, b^{3}}, -\frac{3 \, a^{4} \sqrt{-b} \arctan \left (\frac{\sqrt{-b} x}{\sqrt{b x^{2} + a}}\right ) -{\left (16 \, b^{4} x^{7} + 24 \, a b^{3} x^{5} + 2 \, a^{2} b^{2} x^{3} - 3 \, a^{3} b x\right )} \sqrt{b x^{2} + a}}{128 \, b^{3}}\right ] \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(x^4*(b*x^2+a)^(3/2),x, algorithm="fricas")

[Out]

[1/256*(3*a^4*sqrt(b)*log(-2*b*x^2 - 2*sqrt(b*x^2 + a)*sqrt(b)*x - a) + 2*(16*b^4*x^7 + 24*a*b^3*x^5 + 2*a^2*b
^2*x^3 - 3*a^3*b*x)*sqrt(b*x^2 + a))/b^3, -1/128*(3*a^4*sqrt(-b)*arctan(sqrt(-b)*x/sqrt(b*x^2 + a)) - (16*b^4*
x^7 + 24*a*b^3*x^5 + 2*a^2*b^2*x^3 - 3*a^3*b*x)*sqrt(b*x^2 + a))/b^3]

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Sympy [A]  time = 7.56633, size = 148, normalized size = 1.29 \begin{align*} - \frac{3 a^{\frac{7}{2}} x}{128 b^{2} \sqrt{1 + \frac{b x^{2}}{a}}} - \frac{a^{\frac{5}{2}} x^{3}}{128 b \sqrt{1 + \frac{b x^{2}}{a}}} + \frac{13 a^{\frac{3}{2}} x^{5}}{64 \sqrt{1 + \frac{b x^{2}}{a}}} + \frac{5 \sqrt{a} b x^{7}}{16 \sqrt{1 + \frac{b x^{2}}{a}}} + \frac{3 a^{4} \operatorname{asinh}{\left (\frac{\sqrt{b} x}{\sqrt{a}} \right )}}{128 b^{\frac{5}{2}}} + \frac{b^{2} x^{9}}{8 \sqrt{a} \sqrt{1 + \frac{b x^{2}}{a}}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(x**4*(b*x**2+a)**(3/2),x)

[Out]

-3*a**(7/2)*x/(128*b**2*sqrt(1 + b*x**2/a)) - a**(5/2)*x**3/(128*b*sqrt(1 + b*x**2/a)) + 13*a**(3/2)*x**5/(64*
sqrt(1 + b*x**2/a)) + 5*sqrt(a)*b*x**7/(16*sqrt(1 + b*x**2/a)) + 3*a**4*asinh(sqrt(b)*x/sqrt(a))/(128*b**(5/2)
) + b**2*x**9/(8*sqrt(a)*sqrt(1 + b*x**2/a))

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Giac [A]  time = 2.00105, size = 103, normalized size = 0.9 \begin{align*} \frac{1}{128} \,{\left (2 \,{\left (4 \,{\left (2 \, b x^{2} + 3 \, a\right )} x^{2} + \frac{a^{2}}{b}\right )} x^{2} - \frac{3 \, a^{3}}{b^{2}}\right )} \sqrt{b x^{2} + a} x - \frac{3 \, a^{4} \log \left ({\left | -\sqrt{b} x + \sqrt{b x^{2} + a} \right |}\right )}{128 \, b^{\frac{5}{2}}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(x^4*(b*x^2+a)^(3/2),x, algorithm="giac")

[Out]

1/128*(2*(4*(2*b*x^2 + 3*a)*x^2 + a^2/b)*x^2 - 3*a^3/b^2)*sqrt(b*x^2 + a)*x - 3/128*a^4*log(abs(-sqrt(b)*x + s
qrt(b*x^2 + a)))/b^(5/2)