3.9.45 \(\int \frac {1}{\sqrt {-15-8 x-x^2}} \, dx\) [845]

Optimal. Leaf size=4 \[ \sin ^{-1}(4+x) \]

[Out]

arcsin(4+x)

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Rubi [A]
time = 0.00, antiderivative size = 4, normalized size of antiderivative = 1.00, number of steps used = 2, number of rules used = 2, integrand size = 14, \(\frac {\text {number of rules}}{\text {integrand size}}\) = 0.143, Rules used = {633, 222} \begin {gather*} \text {ArcSin}(x+4) \end {gather*}

Antiderivative was successfully verified.

[In]

Int[1/Sqrt[-15 - 8*x - x^2],x]

[Out]

ArcSin[4 + x]

Rule 222

Int[1/Sqrt[(a_) + (b_.)*(x_)^2], x_Symbol] :> Simp[ArcSin[Rt[-b, 2]*(x/Sqrt[a])]/Rt[-b, 2], x] /; FreeQ[{a, b}
, x] && GtQ[a, 0] && NegQ[b]

Rule 633

Int[((a_.) + (b_.)*(x_) + (c_.)*(x_)^2)^(p_), x_Symbol] :> Dist[1/(2*c*(-4*(c/(b^2 - 4*a*c)))^p), Subst[Int[Si
mp[1 - x^2/(b^2 - 4*a*c), x]^p, x], x, b + 2*c*x], x] /; FreeQ[{a, b, c, p}, x] && GtQ[4*a - b^2/c, 0]

Rubi steps

\begin {align*} \int \frac {1}{\sqrt {-15-8 x-x^2}} \, dx &=-\left (\frac {1}{2} \text {Subst}\left (\int \frac {1}{\sqrt {1-\frac {x^2}{4}}} \, dx,x,-8-2 x\right )\right )\\ &=\sin ^{-1}(4+x)\\ \end {align*}

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Mathematica [B] Leaf count is larger than twice the leaf count of optimal. \(23\) vs. \(2(4)=8\).
time = 0.05, size = 23, normalized size = 5.75 \begin {gather*} -2 \tan ^{-1}\left (\frac {\sqrt {-15-8 x-x^2}}{5+x}\right ) \end {gather*}

Antiderivative was successfully verified.

[In]

Integrate[1/Sqrt[-15 - 8*x - x^2],x]

[Out]

-2*ArcTan[Sqrt[-15 - 8*x - x^2]/(5 + x)]

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Maple [A]
time = 0.56, size = 5, normalized size = 1.25

method	result	size
default	\(\arcsin \left (x +4\right )\)	\(5\)
trager	\(\RootOf \left (\textit {\_Z}^{2}+1\right ) \ln \left (-x \RootOf \left (\textit {\_Z}^{2}+1\right )-4 \RootOf \left (\textit {\_Z}^{2}+1\right )+\sqrt {-x^{2}-8 x -15}\right )\)	\(39\)

Verification of antiderivative is not currently implemented for this CAS.

[In]

int(1/(-x^2-8*x-15)^(1/2),x,method=_RETURNVERBOSE)

[Out]

arcsin(x+4)

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Maxima [A]
time = 0.52, size = 8, normalized size = 2.00 \begin {gather*} -\arcsin \left (-x - 4\right ) \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(-x^2-8*x-15)^(1/2),x, algorithm="maxima")

[Out]

-arcsin(-x - 4)

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Fricas [B] Leaf count of result is larger than twice the leaf count of optimal. 29 vs. \(2 (4) = 8\).
time = 0.34, size = 29, normalized size = 7.25 \begin {gather*} -\arctan \left (\frac {\sqrt {-x^{2} - 8 \, x - 15} {\left (x + 4\right )}}{x^{2} + 8 \, x + 15}\right ) \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(-x^2-8*x-15)^(1/2),x, algorithm="fricas")

[Out]

-arctan(sqrt(-x^2 - 8*x - 15)*(x + 4)/(x^2 + 8*x + 15))

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Sympy [F]
time = 0.00, size = 0, normalized size = 0.00 \begin {gather*} \int \frac {1}{\sqrt {- x^{2} - 8 x - 15}}\, dx \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(-x**2-8*x-15)**(1/2),x)

[Out]

Integral(1/sqrt(-x**2 - 8*x - 15), x)

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Giac [B] Leaf count of result is larger than twice the leaf count of optimal. 24 vs. \(2 (4) = 8\).
time = 2.49, size = 24, normalized size = 6.00 \begin {gather*} \frac {1}{2} \, \sqrt {-x^{2} - 8 \, x - 15} {\left (x + 4\right )} + \frac {1}{2} \, \arcsin \left (x + 4\right ) \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(-x^2-8*x-15)^(1/2),x, algorithm="giac")

[Out]

1/2*sqrt(-x^2 - 8*x - 15)*(x + 4) + 1/2*arcsin(x + 4)

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Mupad [B]
time = 3.18, size = 4, normalized size = 1.00 \begin {gather*} \mathrm {asin}\left (x+4\right ) \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

int(1/(- 8*x - x^2 - 15)^(1/2),x)

[Out]

asin(x + 4)

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