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

Optimal. Leaf size=38 \[ -\frac {\log \left (a+b x^2\right )}{2 a^2}+\frac {\log (x)}{a^2}+\frac {1}{2 a \left (a+b x^2\right )} \]

________________________________________________________________________________________

Rubi [A]  time = 0.03, antiderivative size = 38, normalized size of antiderivative = 1.00, 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 = {1584, 266, 44} \begin {gather*} -\frac {\log \left (a+b x^2\right )}{2 a^2}+\frac {\log (x)}{a^2}+\frac {1}{2 a \left (a+b x^2\right )} \end {gather*}

Antiderivative was successfully verified.

[In]

Int[x/(a*x + b*x^3)^2,x]

[Out]

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

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])

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 1584

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

Rubi steps

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

________________________________________________________________________________________

Mathematica [A]  time = 0.02, size = 33, normalized size = 0.87 \begin {gather*} \frac {\frac {a}{a+b x^2}-\log \left (a+b x^2\right )+2 \log (x)}{2 a^2} \end {gather*}

Antiderivative was successfully verified.

[In]

Integrate[x/(a*x + b*x^3)^2,x]

[Out]

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

________________________________________________________________________________________

IntegrateAlgebraic [F]  time = 0.00, size = 0, normalized size = 0.00 \begin {gather*} \int \frac {x}{\left (a x+b x^3\right )^2} \, dx \end {gather*}

Verification is not applicable to the result.

[In]

IntegrateAlgebraic[x/(a*x + b*x^3)^2,x]

[Out]

IntegrateAlgebraic[x/(a*x + b*x^3)^2, x]

________________________________________________________________________________________

fricas [A]  time = 0.41, size = 47, normalized size = 1.24 \begin {gather*} -\frac {{\left (b x^{2} + a\right )} \log \left (b x^{2} + a\right ) - 2 \, {\left (b x^{2} + a\right )} \log \relax (x) - a}{2 \, {\left (a^{2} b x^{2} + a^{3}\right )}} \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

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

[Out]

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

________________________________________________________________________________________

giac [A]  time = 0.16, size = 47, normalized size = 1.24 \begin {gather*} \frac {\log \left (x^{2}\right )}{2 \, a^{2}} - \frac {\log \left ({\left | b x^{2} + a \right |}\right )}{2 \, a^{2}} + \frac {b x^{2} + 2 \, a}{2 \, {\left (b x^{2} + a\right )} a^{2}} \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

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

[Out]

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

________________________________________________________________________________________

maple [A]  time = 0.05, size = 35, normalized size = 0.92 \begin {gather*} \frac {1}{2 \left (b \,x^{2}+a \right ) a}+\frac {\ln \relax (x )}{a^{2}}-\frac {\ln \left (b \,x^{2}+a \right )}{2 a^{2}} \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

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

[Out]

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

________________________________________________________________________________________

maxima [A]  time = 1.40, size = 34, normalized size = 0.89 \begin {gather*} \frac {1}{2 \, {\left (a b x^{2} + a^{2}\right )}} - \frac {\log \left (b x^{2} + a\right )}{2 \, a^{2}} + \frac {\log \relax (x)}{a^{2}} \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

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

[Out]

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

________________________________________________________________________________________

mupad [B]  time = 0.05, size = 34, normalized size = 0.89 \begin {gather*} \frac {\ln \relax (x)}{a^2}+\frac {1}{2\,a\,\left (b\,x^2+a\right )}-\frac {\ln \left (b\,x^2+a\right )}{2\,a^2} \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

int(x/(a*x + b*x^3)^2,x)

[Out]

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

________________________________________________________________________________________

sympy [A]  time = 0.33, size = 34, normalized size = 0.89 \begin {gather*} \frac {1}{2 a^{2} + 2 a b x^{2}} + \frac {\log {\relax (x )}}{a^{2}} - \frac {\log {\left (\frac {a}{b} + x^{2} \right )}}{2 a^{2}} \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

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

[Out]

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

________________________________________________________________________________________