3.1856 \(\int \frac{1}{(a+\frac{b}{x^2}) x^7} \, dx\)

Optimal. Leaf size=49 \[ -\frac{a^2 \log \left (a x^2+b\right )}{2 b^3}+\frac{a^2 \log (x)}{b^3}+\frac{a}{2 b^2 x^2}-\frac{1}{4 b x^4} \]

[Out]

-1/(4*b*x^4) + a/(2*b^2*x^2) + (a^2*Log[x])/b^3 - (a^2*Log[b + a*x^2])/(2*b^3)

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Rubi [A]  time = 0.0304958, antiderivative size = 49, normalized size of antiderivative = 1., number of steps used = 4, number of rules used = 3, integrand size = 13, \(\frac{\text{number of rules}}{\text{integrand size}}\) = 0.231, Rules used = {263, 266, 44} \[ -\frac{a^2 \log \left (a x^2+b\right )}{2 b^3}+\frac{a^2 \log (x)}{b^3}+\frac{a}{2 b^2 x^2}-\frac{1}{4 b x^4} \]

Antiderivative was successfully verified.

[In]

Int[1/((a + b/x^2)*x^7),x]

[Out]

-1/(4*b*x^4) + a/(2*b^2*x^2) + (a^2*Log[x])/b^3 - (a^2*Log[b + a*x^2])/(2*b^3)

Rule 263

Int[(x_)^(m_.)*((a_) + (b_.)*(x_)^(n_))^(p_), x_Symbol] :> Int[x^(m + n*p)*(b + a/x^n)^p, x] /; FreeQ[{a, b, m
, n}, x] && IntegerQ[p] && NegQ[n]

Rule 266

Int[(x_)^(m_.)*((a_) + (b_.)*(x_)^(n_))^(p_), x_Symbol] :> Dist[1/n, Subst[Int[x^(Simplify[(m + 1)/n] - 1)*(a
+ b*x)^p, x], x, x^n], x] /; FreeQ[{a, b, m, n, p}, x] && IntegerQ[Simplify[(m + 1)/n]]

Rule 44

Int[((a_) + (b_.)*(x_))^(m_.)*((c_.) + (d_.)*(x_))^(n_.), x_Symbol] :> Int[ExpandIntegrand[(a + b*x)^m*(c + d*
x)^n, x], x] /; FreeQ[{a, b, c, d}, x] && NeQ[b*c - a*d, 0] && ILtQ[m, 0] && IntegerQ[n] &&  !(IGtQ[n, 0] && L
tQ[m + n + 2, 0])

Rubi steps

\begin{align*} \int \frac{1}{\left (a+\frac{b}{x^2}\right ) x^7} \, dx &=\int \frac{1}{x^5 \left (b+a x^2\right )} \, dx\\ &=\frac{1}{2} \operatorname{Subst}\left (\int \frac{1}{x^3 (b+a x)} \, dx,x,x^2\right )\\ &=\frac{1}{2} \operatorname{Subst}\left (\int \left (\frac{1}{b x^3}-\frac{a}{b^2 x^2}+\frac{a^2}{b^3 x}-\frac{a^3}{b^3 (b+a x)}\right ) \, dx,x,x^2\right )\\ &=-\frac{1}{4 b x^4}+\frac{a}{2 b^2 x^2}+\frac{a^2 \log (x)}{b^3}-\frac{a^2 \log \left (b+a x^2\right )}{2 b^3}\\ \end{align*}

Mathematica [A]  time = 0.0068308, size = 49, normalized size = 1. \[ -\frac{a^2 \log \left (a x^2+b\right )}{2 b^3}+\frac{a^2 \log (x)}{b^3}+\frac{a}{2 b^2 x^2}-\frac{1}{4 b x^4} \]

Antiderivative was successfully verified.

[In]

Integrate[1/((a + b/x^2)*x^7),x]

[Out]

-1/(4*b*x^4) + a/(2*b^2*x^2) + (a^2*Log[x])/b^3 - (a^2*Log[b + a*x^2])/(2*b^3)

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Maple [A]  time = 0.007, size = 44, normalized size = 0.9 \begin{align*} -{\frac{1}{4\,b{x}^{4}}}+{\frac{a}{2\,{b}^{2}{x}^{2}}}+{\frac{{a}^{2}\ln \left ( x \right ) }{{b}^{3}}}-{\frac{{a}^{2}\ln \left ( a{x}^{2}+b \right ) }{2\,{b}^{3}}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

int(1/(a+1/x^2*b)/x^7,x)

[Out]

-1/4/b/x^4+1/2*a/b^2/x^2+a^2*ln(x)/b^3-1/2*a^2*ln(a*x^2+b)/b^3

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Maxima [A]  time = 0.97715, size = 63, normalized size = 1.29 \begin{align*} -\frac{a^{2} \log \left (a x^{2} + b\right )}{2 \, b^{3}} + \frac{a^{2} \log \left (x^{2}\right )}{2 \, b^{3}} + \frac{2 \, a x^{2} - b}{4 \, b^{2} x^{4}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(a+b/x^2)/x^7,x, algorithm="maxima")

[Out]

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

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Fricas [A]  time = 1.70483, size = 108, normalized size = 2.2 \begin{align*} -\frac{2 \, a^{2} x^{4} \log \left (a x^{2} + b\right ) - 4 \, a^{2} x^{4} \log \left (x\right ) - 2 \, a b x^{2} + b^{2}}{4 \, b^{3} x^{4}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(a+b/x^2)/x^7,x, algorithm="fricas")

[Out]

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

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Sympy [A]  time = 0.62907, size = 42, normalized size = 0.86 \begin{align*} \frac{a^{2} \log{\left (x \right )}}{b^{3}} - \frac{a^{2} \log{\left (x^{2} + \frac{b}{a} \right )}}{2 b^{3}} + \frac{2 a x^{2} - b}{4 b^{2} x^{4}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(a+b/x**2)/x**7,x)

[Out]

a**2*log(x)/b**3 - a**2*log(x**2 + b/a)/(2*b**3) + (2*a*x**2 - b)/(4*b**2*x**4)

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Giac [A]  time = 1.1739, size = 77, normalized size = 1.57 \begin{align*} \frac{a^{2} \log \left (x^{2}\right )}{2 \, b^{3}} - \frac{a^{2} \log \left ({\left | a x^{2} + b \right |}\right )}{2 \, b^{3}} - \frac{3 \, a^{2} x^{4} - 2 \, a b x^{2} + b^{2}}{4 \, b^{3} x^{4}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(a+b/x^2)/x^7,x, algorithm="giac")

[Out]

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