3.1638 \(\int \frac{1}{(a+\frac{b}{x})^3 x} \, dx\)

Optimal. Leaf size=41 \[ -\frac{b^2}{2 a^3 (a x+b)^2}+\frac{2 b}{a^3 (a x+b)}+\frac{\log (a x+b)}{a^3} \]

[Out]

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

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Rubi [A]  time = 0.0222989, antiderivative size = 41, normalized size of antiderivative = 1., number of steps used = 3, number of rules used = 2, integrand size = 13, \(\frac{\text{number of rules}}{\text{integrand size}}\) = 0.154, Rules used = {263, 43} \[ -\frac{b^2}{2 a^3 (a x+b)^2}+\frac{2 b}{a^3 (a x+b)}+\frac{\log (a x+b)}{a^3} \]

Antiderivative was successfully verified.

[In]

Int[1/((a + b/x)^3*x),x]

[Out]

-b^2/(2*a^3*(b + a*x)^2) + (2*b)/(a^3*(b + a*x)) + Log[b + a*x]/a^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 43

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, n}, x] && NeQ[b*c - a*d, 0] && IGtQ[m, 0] && ( !IntegerQ[n] || (EqQ[c, 0]
&& LeQ[7*m + 4*n + 4, 0]) || LtQ[9*m + 5*(n + 1), 0] || GtQ[m + n + 2, 0])

Rubi steps

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

Mathematica [A]  time = 0.0124631, size = 33, normalized size = 0.8 \[ \frac{\frac{b (4 a x+3 b)}{(a x+b)^2}+2 \log (a x+b)}{2 a^3} \]

Antiderivative was successfully verified.

[In]

Integrate[1/((a + b/x)^3*x),x]

[Out]

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

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Maple [A]  time = 0.004, size = 40, normalized size = 1. \begin{align*} -{\frac{{b}^{2}}{2\,{a}^{3} \left ( ax+b \right ) ^{2}}}+2\,{\frac{b}{{a}^{3} \left ( ax+b \right ) }}+{\frac{\ln \left ( ax+b \right ) }{{a}^{3}}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

int(1/(a+b/x)^3/x,x)

[Out]

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

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Maxima [A]  time = 1.07854, size = 65, normalized size = 1.59 \begin{align*} \frac{4 \, a b x + 3 \, b^{2}}{2 \,{\left (a^{5} x^{2} + 2 \, a^{4} b x + a^{3} b^{2}\right )}} + \frac{\log \left (a x + b\right )}{a^{3}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(a+b/x)^3/x,x, algorithm="maxima")

[Out]

1/2*(4*a*b*x + 3*b^2)/(a^5*x^2 + 2*a^4*b*x + a^3*b^2) + log(a*x + b)/a^3

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Fricas [A]  time = 1.68191, size = 132, normalized size = 3.22 \begin{align*} \frac{4 \, a b x + 3 \, b^{2} + 2 \,{\left (a^{2} x^{2} + 2 \, a b x + b^{2}\right )} \log \left (a x + b\right )}{2 \,{\left (a^{5} x^{2} + 2 \, a^{4} b x + a^{3} b^{2}\right )}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(a+b/x)^3/x,x, algorithm="fricas")

[Out]

1/2*(4*a*b*x + 3*b^2 + 2*(a^2*x^2 + 2*a*b*x + b^2)*log(a*x + b))/(a^5*x^2 + 2*a^4*b*x + a^3*b^2)

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Sympy [A]  time = 0.34727, size = 46, normalized size = 1.12 \begin{align*} \frac{4 a b x + 3 b^{2}}{2 a^{5} x^{2} + 4 a^{4} b x + 2 a^{3} b^{2}} + \frac{\log{\left (a x + b \right )}}{a^{3}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(a+b/x)**3/x,x)

[Out]

(4*a*b*x + 3*b**2)/(2*a**5*x**2 + 4*a**4*b*x + 2*a**3*b**2) + log(a*x + b)/a**3

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Giac [A]  time = 1.08731, size = 50, normalized size = 1.22 \begin{align*} \frac{\log \left ({\left | a x + b \right |}\right )}{a^{3}} + \frac{4 \, b x + \frac{3 \, b^{2}}{a}}{2 \,{\left (a x + b\right )}^{2} a^{2}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(a+b/x)^3/x,x, algorithm="giac")

[Out]

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