3.1627 \(\int \frac{1}{(a+\frac{b}{x})^2 x^3} \, dx\)

Optimal. Leaf size=29 \[ -\frac{\log (a x+b)}{b^2}+\frac{1}{b (a x+b)}+\frac{\log (x)}{b^2} \]

[Out]

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

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Rubi [A]  time = 0.0168673, antiderivative size = 29, 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, 44} \[ -\frac{\log (a x+b)}{b^2}+\frac{1}{b (a x+b)}+\frac{\log (x)}{b^2} \]

Antiderivative was successfully verified.

[In]

Int[1/((a + b/x)^2*x^3),x]

[Out]

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

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

Mathematica [A]  time = 0.0095023, size = 24, normalized size = 0.83 \[ \frac{\frac{b}{a x+b}-\log (a x+b)+\log (x)}{b^2} \]

Antiderivative was successfully verified.

[In]

Integrate[1/((a + b/x)^2*x^3),x]

[Out]

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

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Maple [A]  time = 0.008, size = 30, normalized size = 1. \begin{align*}{\frac{1}{b \left ( ax+b \right ) }}+{\frac{\ln \left ( x \right ) }{{b}^{2}}}-{\frac{\ln \left ( ax+b \right ) }{{b}^{2}}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

int(1/(a+b/x)^2/x^3,x)

[Out]

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

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Maxima [A]  time = 1.10529, size = 38, normalized size = 1.31 \begin{align*} \frac{1}{a b x + b^{2}} - \frac{\log \left (a x + b\right )}{b^{2}} + \frac{\log \left (x\right )}{b^{2}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(a+b/x)^2/x^3,x, algorithm="maxima")

[Out]

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

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Fricas [A]  time = 1.4592, size = 89, normalized size = 3.07 \begin{align*} -\frac{{\left (a x + b\right )} \log \left (a x + b\right ) -{\left (a x + b\right )} \log \left (x\right ) - b}{a b^{2} x + b^{3}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(a+b/x)^2/x^3,x, algorithm="fricas")

[Out]

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

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Sympy [A]  time = 0.338869, size = 22, normalized size = 0.76 \begin{align*} \frac{1}{a b x + b^{2}} + \frac{\log{\left (x \right )} - \log{\left (x + \frac{b}{a} \right )}}{b^{2}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(a+b/x)**2/x**3,x)

[Out]

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

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Giac [A]  time = 1.12537, size = 42, normalized size = 1.45 \begin{align*} -\frac{\log \left ({\left | a x + b \right |}\right )}{b^{2}} + \frac{\log \left ({\left | x \right |}\right )}{b^{2}} + \frac{1}{{\left (a x + b\right )} b} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(a+b/x)^2/x^3,x, algorithm="giac")

[Out]

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