3.125 \(\int x^5 \text {erfc}(b x)^2 \, dx\)

Optimal. Leaf size=178 \[ -\frac {5 \text {erfc}(b x)^2}{16 b^6}-\frac {x^5 e^{-b^2 x^2} \text {erfc}(b x)}{3 \sqrt {\pi } b}+\frac {x^4 e^{-2 b^2 x^2}}{6 \pi b^2}+\frac {11 e^{-2 b^2 x^2}}{12 \pi b^6}-\frac {5 x e^{-b^2 x^2} \text {erfc}(b x)}{4 \sqrt {\pi } b^5}+\frac {7 x^2 e^{-2 b^2 x^2}}{12 \pi b^4}-\frac {5 x^3 e^{-b^2 x^2} \text {erfc}(b x)}{6 \sqrt {\pi } b^3}+\frac {1}{6} x^6 \text {erfc}(b x)^2 \]

[Out]

11/12/b^6/exp(2*b^2*x^2)/Pi+7/12*x^2/b^4/exp(2*b^2*x^2)/Pi+1/6*x^4/b^2/exp(2*b^2*x^2)/Pi-5/16*erfc(b*x)^2/b^6+
1/6*x^6*erfc(b*x)^2-5/4*x*erfc(b*x)/b^5/exp(b^2*x^2)/Pi^(1/2)-5/6*x^3*erfc(b*x)/b^3/exp(b^2*x^2)/Pi^(1/2)-1/3*
x^5*erfc(b*x)/b/exp(b^2*x^2)/Pi^(1/2)

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Rubi [A]  time = 0.28, antiderivative size = 178, normalized size of antiderivative = 1.00, number of steps used = 12, number of rules used = 6, integrand size = 10, \(\frac {\text {number of rules}}{\text {integrand size}}\) = 0.600, Rules used = {6365, 6386, 6374, 30, 2209, 2212} \[ -\frac {x^5 e^{-b^2 x^2} \text {Erfc}(b x)}{3 \sqrt {\pi } b}-\frac {5 x^3 e^{-b^2 x^2} \text {Erfc}(b x)}{6 \sqrt {\pi } b^3}-\frac {5 x e^{-b^2 x^2} \text {Erfc}(b x)}{4 \sqrt {\pi } b^5}-\frac {5 \text {Erfc}(b x)^2}{16 b^6}+\frac {x^4 e^{-2 b^2 x^2}}{6 \pi b^2}+\frac {7 x^2 e^{-2 b^2 x^2}}{12 \pi b^4}+\frac {11 e^{-2 b^2 x^2}}{12 \pi b^6}+\frac {1}{6} x^6 \text {Erfc}(b x)^2 \]

Antiderivative was successfully verified.

[In]

Int[x^5*Erfc[b*x]^2,x]

[Out]

11/(12*b^6*E^(2*b^2*x^2)*Pi) + (7*x^2)/(12*b^4*E^(2*b^2*x^2)*Pi) + x^4/(6*b^2*E^(2*b^2*x^2)*Pi) - (5*x*Erfc[b*
x])/(4*b^5*E^(b^2*x^2)*Sqrt[Pi]) - (5*x^3*Erfc[b*x])/(6*b^3*E^(b^2*x^2)*Sqrt[Pi]) - (x^5*Erfc[b*x])/(3*b*E^(b^
2*x^2)*Sqrt[Pi]) - (5*Erfc[b*x]^2)/(16*b^6) + (x^6*Erfc[b*x]^2)/6

Rule 30

Int[(x_)^(m_.), x_Symbol] :> Simp[x^(m + 1)/(m + 1), x] /; FreeQ[m, x] && NeQ[m, -1]

Rule 2209

Int[(F_)^((a_.) + (b_.)*((c_.) + (d_.)*(x_))^(n_))*((e_.) + (f_.)*(x_))^(m_.), x_Symbol] :> Simp[((e + f*x)^n*
F^(a + b*(c + d*x)^n))/(b*f*n*(c + d*x)^n*Log[F]), x] /; FreeQ[{F, a, b, c, d, e, f, n}, x] && EqQ[m, n - 1] &
& EqQ[d*e - c*f, 0]

Rule 2212

Int[(F_)^((a_.) + (b_.)*((c_.) + (d_.)*(x_))^(n_))*((c_.) + (d_.)*(x_))^(m_.), x_Symbol] :> Simp[((c + d*x)^(m
- n + 1)*F^(a + b*(c + d*x)^n))/(b*d*n*Log[F]), x] - Dist[(m - n + 1)/(b*n*Log[F]), Int[(c + d*x)^(m - n)*F^(
a + b*(c + d*x)^n), x], x] /; FreeQ[{F, a, b, c, d}, x] && IntegerQ[(2*(m + 1))/n] && LtQ[0, (m + 1)/n, 5] &&
IntegerQ[n] && (LtQ[0, n, m + 1] || LtQ[m, n, 0])

Rule 6365

Int[Erfc[(b_.)*(x_)]^2*(x_)^(m_.), x_Symbol] :> Simp[(x^(m + 1)*Erfc[b*x]^2)/(m + 1), x] + Dist[(4*b)/(Sqrt[Pi
]*(m + 1)), Int[(x^(m + 1)*Erfc[b*x])/E^(b^2*x^2), x], x] /; FreeQ[b, x] && (IGtQ[m, 0] || ILtQ[(m + 1)/2, 0])

Rule 6374

Int[E^((c_.) + (d_.)*(x_)^2)*Erfc[(b_.)*(x_)]^(n_.), x_Symbol] :> -Dist[(E^c*Sqrt[Pi])/(2*b), Subst[Int[x^n, x
], x, Erfc[b*x]], x] /; FreeQ[{b, c, d, n}, x] && EqQ[d, -b^2]

Rule 6386

Int[E^((c_.) + (d_.)*(x_)^2)*Erfc[(a_.) + (b_.)*(x_)]*(x_)^(m_), x_Symbol] :> Simp[(x^(m - 1)*E^(c + d*x^2)*Er
fc[a + b*x])/(2*d), x] + (-Dist[(m - 1)/(2*d), Int[x^(m - 2)*E^(c + d*x^2)*Erfc[a + b*x], x], x] + Dist[b/(d*S
qrt[Pi]), Int[x^(m - 1)*E^(-a^2 + c - 2*a*b*x - (b^2 - d)*x^2), x], x]) /; FreeQ[{a, b, c, d}, x] && IGtQ[m, 1
]

Rubi steps

\begin {align*} \int x^5 \text {erfc}(b x)^2 \, dx &=\frac {1}{6} x^6 \text {erfc}(b x)^2+\frac {(2 b) \int e^{-b^2 x^2} x^6 \text {erfc}(b x) \, dx}{3 \sqrt {\pi }}\\ &=-\frac {e^{-b^2 x^2} x^5 \text {erfc}(b x)}{3 b \sqrt {\pi }}+\frac {1}{6} x^6 \text {erfc}(b x)^2-\frac {2 \int e^{-2 b^2 x^2} x^5 \, dx}{3 \pi }+\frac {5 \int e^{-b^2 x^2} x^4 \text {erfc}(b x) \, dx}{3 b \sqrt {\pi }}\\ &=\frac {e^{-2 b^2 x^2} x^4}{6 b^2 \pi }-\frac {5 e^{-b^2 x^2} x^3 \text {erfc}(b x)}{6 b^3 \sqrt {\pi }}-\frac {e^{-b^2 x^2} x^5 \text {erfc}(b x)}{3 b \sqrt {\pi }}+\frac {1}{6} x^6 \text {erfc}(b x)^2-\frac {2 \int e^{-2 b^2 x^2} x^3 \, dx}{3 b^2 \pi }-\frac {5 \int e^{-2 b^2 x^2} x^3 \, dx}{3 b^2 \pi }+\frac {5 \int e^{-b^2 x^2} x^2 \text {erfc}(b x) \, dx}{2 b^3 \sqrt {\pi }}\\ &=\frac {7 e^{-2 b^2 x^2} x^2}{12 b^4 \pi }+\frac {e^{-2 b^2 x^2} x^4}{6 b^2 \pi }-\frac {5 e^{-b^2 x^2} x \text {erfc}(b x)}{4 b^5 \sqrt {\pi }}-\frac {5 e^{-b^2 x^2} x^3 \text {erfc}(b x)}{6 b^3 \sqrt {\pi }}-\frac {e^{-b^2 x^2} x^5 \text {erfc}(b x)}{3 b \sqrt {\pi }}+\frac {1}{6} x^6 \text {erfc}(b x)^2-\frac {\int e^{-2 b^2 x^2} x \, dx}{3 b^4 \pi }-\frac {5 \int e^{-2 b^2 x^2} x \, dx}{6 b^4 \pi }-\frac {5 \int e^{-2 b^2 x^2} x \, dx}{2 b^4 \pi }+\frac {5 \int e^{-b^2 x^2} \text {erfc}(b x) \, dx}{4 b^5 \sqrt {\pi }}\\ &=\frac {11 e^{-2 b^2 x^2}}{12 b^6 \pi }+\frac {7 e^{-2 b^2 x^2} x^2}{12 b^4 \pi }+\frac {e^{-2 b^2 x^2} x^4}{6 b^2 \pi }-\frac {5 e^{-b^2 x^2} x \text {erfc}(b x)}{4 b^5 \sqrt {\pi }}-\frac {5 e^{-b^2 x^2} x^3 \text {erfc}(b x)}{6 b^3 \sqrt {\pi }}-\frac {e^{-b^2 x^2} x^5 \text {erfc}(b x)}{3 b \sqrt {\pi }}+\frac {1}{6} x^6 \text {erfc}(b x)^2-\frac {5 \operatorname {Subst}(\int x \, dx,x,\text {erfc}(b x))}{8 b^6}\\ &=\frac {11 e^{-2 b^2 x^2}}{12 b^6 \pi }+\frac {7 e^{-2 b^2 x^2} x^2}{12 b^4 \pi }+\frac {e^{-2 b^2 x^2} x^4}{6 b^2 \pi }-\frac {5 e^{-b^2 x^2} x \text {erfc}(b x)}{4 b^5 \sqrt {\pi }}-\frac {5 e^{-b^2 x^2} x^3 \text {erfc}(b x)}{6 b^3 \sqrt {\pi }}-\frac {e^{-b^2 x^2} x^5 \text {erfc}(b x)}{3 b \sqrt {\pi }}-\frac {5 \text {erfc}(b x)^2}{16 b^6}+\frac {1}{6} x^6 \text {erfc}(b x)^2\\ \end {align*}

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Mathematica [A]  time = 0.47, size = 173, normalized size = 0.97 \[ \frac {1}{24} \left (\left (\frac {15}{b^6}-8 x^6\right ) \text {erf}(b x)+\frac {e^{-2 b^2 x^2} \left (8 b^4 x^4-15 \pi e^{2 b^2 x^2} \text {erf}(b x)^2+28 b^2 x^2+4 \sqrt {\pi } b x e^{b^2 x^2} \left (4 b^4 x^4+10 b^2 x^2+15\right ) \text {erf}(b x)+44\right )}{2 \pi b^6}-\frac {2 x e^{-b^2 x^2} \left (4 b^4 x^4+10 b^2 x^2+15\right )}{\sqrt {\pi } b^5}+4 x^6 \text {erf}(b x)^2+4 x^6\right ) \]

Warning: Unable to verify antiderivative.

[In]

Integrate[x^5*Erfc[b*x]^2,x]

[Out]

(4*x^6 - (2*x*(15 + 10*b^2*x^2 + 4*b^4*x^4))/(b^5*E^(b^2*x^2)*Sqrt[Pi]) + (15/b^6 - 8*x^6)*Erf[b*x] + 4*x^6*Er
f[b*x]^2 + (44 + 28*b^2*x^2 + 8*b^4*x^4 + 4*b*E^(b^2*x^2)*Sqrt[Pi]*x*(15 + 10*b^2*x^2 + 4*b^4*x^4)*Erf[b*x] -
15*E^(2*b^2*x^2)*Pi*Erf[b*x]^2)/(2*b^6*E^(2*b^2*x^2)*Pi))/24

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fricas [A]  time = 0.42, size = 149, normalized size = 0.84 \[ \frac {8 \, \pi b^{6} x^{6} - {\left (15 \, \pi - 8 \, \pi b^{6} x^{6}\right )} \operatorname {erf}\left (b x\right )^{2} - 4 \, \sqrt {\pi } {\left (4 \, b^{5} x^{5} + 10 \, b^{3} x^{3} + 15 \, b x - {\left (4 \, b^{5} x^{5} + 10 \, b^{3} x^{3} + 15 \, b x\right )} \operatorname {erf}\left (b x\right )\right )} e^{\left (-b^{2} x^{2}\right )} + 2 \, {\left (15 \, \pi - 8 \, \pi b^{6} x^{6}\right )} \operatorname {erf}\left (b x\right ) + 4 \, {\left (2 \, b^{4} x^{4} + 7 \, b^{2} x^{2} + 11\right )} e^{\left (-2 \, b^{2} x^{2}\right )}}{48 \, \pi b^{6}} \]

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(x^5*erfc(b*x)^2,x, algorithm="fricas")

[Out]

1/48*(8*pi*b^6*x^6 - (15*pi - 8*pi*b^6*x^6)*erf(b*x)^2 - 4*sqrt(pi)*(4*b^5*x^5 + 10*b^3*x^3 + 15*b*x - (4*b^5*
x^5 + 10*b^3*x^3 + 15*b*x)*erf(b*x))*e^(-b^2*x^2) + 2*(15*pi - 8*pi*b^6*x^6)*erf(b*x) + 4*(2*b^4*x^4 + 7*b^2*x
^2 + 11)*e^(-2*b^2*x^2))/(pi*b^6)

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giac [F]  time = 0.00, size = 0, normalized size = 0.00 \[ \int x^{5} \operatorname {erfc}\left (b x\right )^{2}\,{d x} \]

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(x^5*erfc(b*x)^2,x, algorithm="giac")

[Out]

integrate(x^5*erfc(b*x)^2, x)

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maple [F]  time = 0.02, size = 0, normalized size = 0.00 \[ \int x^{5} \mathrm {erfc}\left (b x \right )^{2}\, dx \]

Verification of antiderivative is not currently implemented for this CAS.

[In]

int(x^5*erfc(b*x)^2,x)

[Out]

int(x^5*erfc(b*x)^2,x)

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maxima [F]  time = 0.00, size = 0, normalized size = 0.00 \[ \int x^{5} \operatorname {erfc}\left (b x\right )^{2}\,{d x} \]

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(x^5*erfc(b*x)^2,x, algorithm="maxima")

[Out]

integrate(x^5*erfc(b*x)^2, x)

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mupad [B]  time = 0.32, size = 143, normalized size = 0.80 \[ \frac {x^6\,{\mathrm {erfc}\left (b\,x\right )}^2}{6}-\frac {\frac {5\,\pi \,{\mathrm {erfc}\left (b\,x\right )}^2}{16}-\frac {11\,{\mathrm {e}}^{-2\,b^2\,x^2}}{12}-\frac {7\,b^2\,x^2\,{\mathrm {e}}^{-2\,b^2\,x^2}}{12}-\frac {b^4\,x^4\,{\mathrm {e}}^{-2\,b^2\,x^2}}{6}+\frac {5\,b^3\,x^3\,\sqrt {\pi }\,{\mathrm {e}}^{-b^2\,x^2}\,\mathrm {erfc}\left (b\,x\right )}{6}+\frac {b^5\,x^5\,\sqrt {\pi }\,{\mathrm {e}}^{-b^2\,x^2}\,\mathrm {erfc}\left (b\,x\right )}{3}+\frac {5\,b\,x\,\sqrt {\pi }\,{\mathrm {e}}^{-b^2\,x^2}\,\mathrm {erfc}\left (b\,x\right )}{4}}{b^6\,\pi } \]

Verification of antiderivative is not currently implemented for this CAS.

[In]

int(x^5*erfc(b*x)^2,x)

[Out]

(x^6*erfc(b*x)^2)/6 - ((5*pi*erfc(b*x)^2)/16 - (11*exp(-2*b^2*x^2))/12 - (7*b^2*x^2*exp(-2*b^2*x^2))/12 - (b^4
*x^4*exp(-2*b^2*x^2))/6 + (5*b^3*x^3*pi^(1/2)*exp(-b^2*x^2)*erfc(b*x))/6 + (b^5*x^5*pi^(1/2)*exp(-b^2*x^2)*erf
c(b*x))/3 + (5*b*x*pi^(1/2)*exp(-b^2*x^2)*erfc(b*x))/4)/(b^6*pi)

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sympy [A]  time = 5.09, size = 172, normalized size = 0.97 \[ \begin {cases} \frac {x^{6} \operatorname {erfc}^{2}{\left (b x \right )}}{6} - \frac {x^{5} e^{- b^{2} x^{2}} \operatorname {erfc}{\left (b x \right )}}{3 \sqrt {\pi } b} + \frac {x^{4} e^{- 2 b^{2} x^{2}}}{6 \pi b^{2}} - \frac {5 x^{3} e^{- b^{2} x^{2}} \operatorname {erfc}{\left (b x \right )}}{6 \sqrt {\pi } b^{3}} + \frac {7 x^{2} e^{- 2 b^{2} x^{2}}}{12 \pi b^{4}} - \frac {5 x e^{- b^{2} x^{2}} \operatorname {erfc}{\left (b x \right )}}{4 \sqrt {\pi } b^{5}} - \frac {5 \operatorname {erfc}^{2}{\left (b x \right )}}{16 b^{6}} + \frac {11 e^{- 2 b^{2} x^{2}}}{12 \pi b^{6}} & \text {for}\: b \neq 0 \\\frac {x^{6}}{6} & \text {otherwise} \end {cases} \]

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(x**5*erfc(b*x)**2,x)

[Out]

Piecewise((x**6*erfc(b*x)**2/6 - x**5*exp(-b**2*x**2)*erfc(b*x)/(3*sqrt(pi)*b) + x**4*exp(-2*b**2*x**2)/(6*pi*
b**2) - 5*x**3*exp(-b**2*x**2)*erfc(b*x)/(6*sqrt(pi)*b**3) + 7*x**2*exp(-2*b**2*x**2)/(12*pi*b**4) - 5*x*exp(-
b**2*x**2)*erfc(b*x)/(4*sqrt(pi)*b**5) - 5*erfc(b*x)**2/(16*b**6) + 11*exp(-2*b**2*x**2)/(12*pi*b**6), Ne(b, 0
)), (x**6/6, True))

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