3.742 \(\int x^{-1+n} (a+b x)^{-n} \, dx\)

Optimal. Leaf size=39 \[ \frac{x^n (a+b x)^{-n} \left (\frac{b x}{a}+1\right )^n \, _2F_1\left (n,n;n+1;-\frac{b x}{a}\right )}{n} \]

[Out]

(x^n*(1 + (b*x)/a)^n*Hypergeometric2F1[n, n, 1 + n, -((b*x)/a)])/(n*(a + b*x)^n)

________________________________________________________________________________________

Rubi [A]  time = 0.0097928, antiderivative size = 39, normalized size of antiderivative = 1., number of steps used = 2, number of rules used = 2, integrand size = 15, \(\frac{\text{number of rules}}{\text{integrand size}}\) = 0.133, Rules used = {66, 64} \[ \frac{x^n (a+b x)^{-n} \left (\frac{b x}{a}+1\right )^n \, _2F_1\left (n,n;n+1;-\frac{b x}{a}\right )}{n} \]

Antiderivative was successfully verified.

[In]

Int[x^(-1 + n)/(a + b*x)^n,x]

[Out]

(x^n*(1 + (b*x)/a)^n*Hypergeometric2F1[n, n, 1 + n, -((b*x)/a)])/(n*(a + b*x)^n)

Rule 66

Int[((b_.)*(x_))^(m_)*((c_) + (d_.)*(x_))^(n_), x_Symbol] :> Dist[(c^IntPart[n]*(c + d*x)^FracPart[n])/(1 + (d
*x)/c)^FracPart[n], Int[(b*x)^m*(1 + (d*x)/c)^n, x], x] /; FreeQ[{b, c, d, m, n}, x] &&  !IntegerQ[m] &&  !Int
egerQ[n] &&  !GtQ[c, 0] &&  !GtQ[-(d/(b*c)), 0] && ((RationalQ[m] &&  !(EqQ[n, -2^(-1)] && EqQ[c^2 - d^2, 0]))
||  !RationalQ[n])

Rule 64

Int[((b_.)*(x_))^(m_)*((c_) + (d_.)*(x_))^(n_), x_Symbol] :> Simp[(c^n*(b*x)^(m + 1)*Hypergeometric2F1[-n, m +
1, m + 2, -((d*x)/c)])/(b*(m + 1)), x] /; FreeQ[{b, c, d, m, n}, x] &&  !IntegerQ[m] && (IntegerQ[n] || (GtQ[
c, 0] &&  !(EqQ[n, -2^(-1)] && EqQ[c^2 - d^2, 0] && GtQ[-(d/(b*c)), 0])))

Rubi steps

\begin{align*} \int x^{-1+n} (a+b x)^{-n} \, dx &=\left ((a+b x)^{-n} \left (1+\frac{b x}{a}\right )^n\right ) \int x^{-1+n} \left (1+\frac{b x}{a}\right )^{-n} \, dx\\ &=\frac{x^n (a+b x)^{-n} \left (1+\frac{b x}{a}\right )^n \, _2F_1\left (n,n;1+n;-\frac{b x}{a}\right )}{n}\\ \end{align*}

Mathematica [A]  time = 0.0071447, size = 39, normalized size = 1. \[ \frac{x^n (a+b x)^{-n} \left (\frac{b x}{a}+1\right )^n \, _2F_1\left (n,n;n+1;-\frac{b x}{a}\right )}{n} \]

Antiderivative was successfully verified.

[In]

Integrate[x^(-1 + n)/(a + b*x)^n,x]

[Out]

(x^n*(1 + (b*x)/a)^n*Hypergeometric2F1[n, n, 1 + n, -((b*x)/a)])/(n*(a + b*x)^n)

________________________________________________________________________________________

Maple [F]  time = 0.047, size = 0, normalized size = 0. \begin{align*} \int{\frac{{x}^{-1+n}}{ \left ( bx+a \right ) ^{n}}}\, dx \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

int(x^(-1+n)/((b*x+a)^n),x)

[Out]

int(x^(-1+n)/((b*x+a)^n),x)

________________________________________________________________________________________

Maxima [F]  time = 0., size = 0, normalized size = 0. \begin{align*} \int \frac{x^{n - 1}}{{\left (b x + a\right )}^{n}}\,{d x} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(x^(-1+n)/((b*x+a)^n),x, algorithm="maxima")

[Out]

integrate(x^(n - 1)/(b*x + a)^n, x)

________________________________________________________________________________________

Fricas [F]  time = 0., size = 0, normalized size = 0. \begin{align*}{\rm integral}\left (\frac{x^{n - 1}}{{\left (b x + a\right )}^{n}}, x\right ) \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(x^(-1+n)/((b*x+a)^n),x, algorithm="fricas")

[Out]

integral(x^(n - 1)/(b*x + a)^n, x)

________________________________________________________________________________________

Sympy [F(-1)]  time = 0., size = 0, normalized size = 0. \begin{align*} \text{Timed out} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(x**(-1+n)/((b*x+a)**n),x)

[Out]

Timed out

________________________________________________________________________________________

Giac [F]  time = 0., size = 0, normalized size = 0. \begin{align*} \int \frac{x^{n - 1}}{{\left (b x + a\right )}^{n}}\,{d x} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(x^(-1+n)/((b*x+a)^n),x, algorithm="giac")

[Out]

integrate(x^(n - 1)/(b*x + a)^n, x)