\(\int \cot ^3(x) \sqrt {a+b \cot ^2(x)} \, dx\) [19]

Optimal result
Mathematica [A] (verified)
Rubi [A] (verified)
Maple [A] (verified)
Fricas [B] (verification not implemented)
Sympy [F]
Maxima [F(-2)]
Giac [B] (verification not implemented)
Mupad [B] (verification not implemented)
Reduce [F]

Optimal result

Integrand size = 17, antiderivative size = 66 \[ \int \cot ^3(x) \sqrt {a+b \cot ^2(x)} \, dx=-\sqrt {a-b} \text {arctanh}\left (\frac {\sqrt {a+b \cot ^2(x)}}{\sqrt {a-b}}\right )+\sqrt {a+b \cot ^2(x)}-\frac {\left (a+b \cot ^2(x)\right )^{3/2}}{3 b} \] Output:

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

Mathematica [A] (verified)

Time = 0.11 (sec) , antiderivative size = 65, normalized size of antiderivative = 0.98 \[ \int \cot ^3(x) \sqrt {a+b \cot ^2(x)} \, dx=-\sqrt {a-b} \text {arctanh}\left (\frac {\sqrt {a+b \cot ^2(x)}}{\sqrt {a-b}}\right )-\frac {\sqrt {a+b \cot ^2(x)} \left (a-3 b+b \cot ^2(x)\right )}{3 b} \] Input:

Integrate[Cot[x]^3*Sqrt[a + b*Cot[x]^2],x]
 

Output:

-(Sqrt[a - b]*ArcTanh[Sqrt[a + b*Cot[x]^2]/Sqrt[a - b]]) - (Sqrt[a + b*Cot 
[x]^2]*(a - 3*b + b*Cot[x]^2))/(3*b)
 

Rubi [A] (verified)

Time = 0.31 (sec) , antiderivative size = 72, normalized size of antiderivative = 1.09, number of steps used = 10, number of rules used = 9, \(\frac {\text {number of rules}}{\text {integrand size}}\) = 0.529, Rules used = {3042, 25, 4153, 25, 354, 90, 60, 73, 221}

Below are the steps used by Rubi to obtain the solution. The rule number used for the transformation is given above next to the arrow. The rules definitions used are listed below.

\(\displaystyle \int \cot ^3(x) \sqrt {a+b \cot ^2(x)} \, dx\)

\(\Big \downarrow \) 3042

\(\displaystyle \int -\tan \left (x+\frac {\pi }{2}\right )^3 \sqrt {a+b \tan \left (x+\frac {\pi }{2}\right )^2}dx\)

\(\Big \downarrow \) 25

\(\displaystyle -\int \tan \left (x+\frac {\pi }{2}\right )^3 \sqrt {b \tan \left (x+\frac {\pi }{2}\right )^2+a}dx\)

\(\Big \downarrow \) 4153

\(\displaystyle \int -\frac {\cot ^3(x) \sqrt {a+b \cot ^2(x)}}{\cot ^2(x)+1}d\cot (x)\)

\(\Big \downarrow \) 25

\(\displaystyle -\int \frac {\cot ^3(x) \sqrt {b \cot ^2(x)+a}}{\cot ^2(x)+1}d\cot (x)\)

\(\Big \downarrow \) 354

\(\displaystyle -\frac {1}{2} \int \frac {\cot ^2(x) \sqrt {b \cot ^2(x)+a}}{\cot ^2(x)+1}d\cot ^2(x)\)

\(\Big \downarrow \) 90

\(\displaystyle \frac {1}{2} \left (\int \frac {\sqrt {b \cot ^2(x)+a}}{\cot ^2(x)+1}d\cot ^2(x)-\frac {2 \left (a+b \cot ^2(x)\right )^{3/2}}{3 b}\right )\)

\(\Big \downarrow \) 60

\(\displaystyle \frac {1}{2} \left ((a-b) \int \frac {1}{\left (\cot ^2(x)+1\right ) \sqrt {b \cot ^2(x)+a}}d\cot ^2(x)-\frac {2 \left (a+b \cot ^2(x)\right )^{3/2}}{3 b}+2 \sqrt {a+b \cot ^2(x)}\right )\)

\(\Big \downarrow \) 73

\(\displaystyle \frac {1}{2} \left (\frac {2 (a-b) \int \frac {1}{\frac {\cot ^4(x)}{b}-\frac {a}{b}+1}d\sqrt {b \cot ^2(x)+a}}{b}-\frac {2 \left (a+b \cot ^2(x)\right )^{3/2}}{3 b}+2 \sqrt {a+b \cot ^2(x)}\right )\)

\(\Big \downarrow \) 221

\(\displaystyle \frac {1}{2} \left (-2 \sqrt {a-b} \text {arctanh}\left (\frac {\sqrt {a+b \cot ^2(x)}}{\sqrt {a-b}}\right )-\frac {2 \left (a+b \cot ^2(x)\right )^{3/2}}{3 b}+2 \sqrt {a+b \cot ^2(x)}\right )\)

Input:

Int[Cot[x]^3*Sqrt[a + b*Cot[x]^2],x]
 

Output:

(-2*Sqrt[a - b]*ArcTanh[Sqrt[a + b*Cot[x]^2]/Sqrt[a - b]] + 2*Sqrt[a + b*C 
ot[x]^2] - (2*(a + b*Cot[x]^2)^(3/2))/(3*b))/2
 

Defintions of rubi rules used

rule 25
Int[-(Fx_), x_Symbol] :> Simp[Identity[-1]   Int[Fx, x], x]
 

rule 60
Int[((a_.) + (b_.)*(x_))^(m_)*((c_.) + (d_.)*(x_))^(n_), x_Symbol] :> Simp[ 
(a + b*x)^(m + 1)*((c + d*x)^n/(b*(m + n + 1))), x] + Simp[n*((b*c - a*d)/( 
b*(m + n + 1)))   Int[(a + b*x)^m*(c + d*x)^(n - 1), x], x] /; FreeQ[{a, b, 
 c, d}, x] && GtQ[n, 0] && NeQ[m + n + 1, 0] &&  !(IGtQ[m, 0] && ( !Integer 
Q[n] || (GtQ[m, 0] && LtQ[m - n, 0]))) &&  !ILtQ[m + n + 2, 0] && IntLinear 
Q[a, b, c, d, m, n, x]
 

rule 73
Int[((a_.) + (b_.)*(x_))^(m_)*((c_.) + (d_.)*(x_))^(n_), x_Symbol] :> With[ 
{p = Denominator[m]}, Simp[p/b   Subst[Int[x^(p*(m + 1) - 1)*(c - a*(d/b) + 
 d*(x^p/b))^n, x], x, (a + b*x)^(1/p)], x]] /; FreeQ[{a, b, c, d}, x] && Lt 
Q[-1, m, 0] && LeQ[-1, n, 0] && LeQ[Denominator[n], Denominator[m]] && IntL 
inearQ[a, b, c, d, m, n, x]
 

rule 90
Int[((a_.) + (b_.)*(x_))*((c_.) + (d_.)*(x_))^(n_.)*((e_.) + (f_.)*(x_))^(p 
_.), x_] :> Simp[b*(c + d*x)^(n + 1)*((e + f*x)^(p + 1)/(d*f*(n + p + 2))), 
 x] + Simp[(a*d*f*(n + p + 2) - b*(d*e*(n + 1) + c*f*(p + 1)))/(d*f*(n + p 
+ 2))   Int[(c + d*x)^n*(e + f*x)^p, x], x] /; FreeQ[{a, b, c, d, e, f, n, 
p}, x] && NeQ[n + p + 2, 0]
 

rule 221
Int[((a_) + (b_.)*(x_)^2)^(-1), x_Symbol] :> Simp[(Rt[-a/b, 2]/a)*ArcTanh[x 
/Rt[-a/b, 2]], x] /; FreeQ[{a, b}, x] && NegQ[a/b]
 

rule 354
Int[(x_)^(m_.)*((a_) + (b_.)*(x_)^2)^(p_.)*((c_) + (d_.)*(x_)^2)^(q_.), x_S 
ymbol] :> Simp[1/2   Subst[Int[x^((m - 1)/2)*(a + b*x)^p*(c + d*x)^q, x], x 
, x^2], x] /; FreeQ[{a, b, c, d, p, q}, x] && NeQ[b*c - a*d, 0] && IntegerQ 
[(m - 1)/2]
 

rule 3042
Int[u_, x_Symbol] :> Int[DeactivateTrig[u, x], x] /; FunctionOfTrigOfLinear 
Q[u, x]
 

rule 4153
Int[((d_.)*tan[(e_.) + (f_.)*(x_)])^(m_.)*((a_) + (b_.)*((c_.)*tan[(e_.) + 
(f_.)*(x_)])^(n_))^(p_.), x_Symbol] :> With[{ff = FreeFactors[Tan[e + f*x], 
 x]}, Simp[c*(ff/f)   Subst[Int[(d*ff*(x/c))^m*((a + b*(ff*x)^n)^p/(c^2 + f 
f^2*x^2)), x], x, c*(Tan[e + f*x]/ff)], x]] /; FreeQ[{a, b, c, d, e, f, m, 
n, p}, x] && (IGtQ[p, 0] || EqQ[n, 2] || EqQ[n, 4] || (IntegerQ[p] && Ratio 
nalQ[n]))
 
Maple [A] (verified)

Time = 0.33 (sec) , antiderivative size = 84, normalized size of antiderivative = 1.27

method result size
derivativedivides \(-\frac {\left (a +b \cot \left (x \right )^{2}\right )^{\frac {3}{2}}}{3 b}+\sqrt {a +b \cot \left (x \right )^{2}}-\frac {b \arctan \left (\frac {\sqrt {a +b \cot \left (x \right )^{2}}}{\sqrt {-a +b}}\right )}{\sqrt {-a +b}}+\frac {a \arctan \left (\frac {\sqrt {a +b \cot \left (x \right )^{2}}}{\sqrt {-a +b}}\right )}{\sqrt {-a +b}}\) \(84\)
default \(-\frac {\left (a +b \cot \left (x \right )^{2}\right )^{\frac {3}{2}}}{3 b}+\sqrt {a +b \cot \left (x \right )^{2}}-\frac {b \arctan \left (\frac {\sqrt {a +b \cot \left (x \right )^{2}}}{\sqrt {-a +b}}\right )}{\sqrt {-a +b}}+\frac {a \arctan \left (\frac {\sqrt {a +b \cot \left (x \right )^{2}}}{\sqrt {-a +b}}\right )}{\sqrt {-a +b}}\) \(84\)

Input:

int(cot(x)^3*(a+b*cot(x)^2)^(1/2),x,method=_RETURNVERBOSE)
 

Output:

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

Fricas [B] (verification not implemented)

Leaf count of result is larger than twice the leaf count of optimal. 141 vs. \(2 (54) = 108\).

Time = 0.13 (sec) , antiderivative size = 330, normalized size of antiderivative = 5.00 \[ \int \cot ^3(x) \sqrt {a+b \cot ^2(x)} \, dx=\left [\frac {3 \, {\left (b \cos \left (2 \, x\right ) - b\right )} \sqrt {a - b} \log \left (-2 \, {\left (a^{2} - 2 \, a b + b^{2}\right )} \cos \left (2 \, x\right )^{2} - 2 \, a^{2} + b^{2} + 2 \, {\left ({\left (a - b\right )} \cos \left (2 \, x\right )^{2} - {\left (2 \, a - b\right )} \cos \left (2 \, x\right ) + a\right )} \sqrt {a - b} \sqrt {\frac {{\left (a - b\right )} \cos \left (2 \, x\right ) - a - b}{\cos \left (2 \, x\right ) - 1}} + 4 \, {\left (a^{2} - a b\right )} \cos \left (2 \, x\right )\right ) - 4 \, {\left ({\left (a - 4 \, b\right )} \cos \left (2 \, x\right ) - a + 2 \, b\right )} \sqrt {\frac {{\left (a - b\right )} \cos \left (2 \, x\right ) - a - b}{\cos \left (2 \, x\right ) - 1}}}{12 \, {\left (b \cos \left (2 \, x\right ) - b\right )}}, -\frac {3 \, {\left (b \cos \left (2 \, x\right ) - b\right )} \sqrt {-a + b} \arctan \left (-\frac {\sqrt {-a + b} \sqrt {\frac {{\left (a - b\right )} \cos \left (2 \, x\right ) - a - b}{\cos \left (2 \, x\right ) - 1}} {\left (\cos \left (2 \, x\right ) - 1\right )}}{{\left (a - b\right )} \cos \left (2 \, x\right ) - a}\right ) + 2 \, {\left ({\left (a - 4 \, b\right )} \cos \left (2 \, x\right ) - a + 2 \, b\right )} \sqrt {\frac {{\left (a - b\right )} \cos \left (2 \, x\right ) - a - b}{\cos \left (2 \, x\right ) - 1}}}{6 \, {\left (b \cos \left (2 \, x\right ) - b\right )}}\right ] \] Input:

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

Output:

[1/12*(3*(b*cos(2*x) - b)*sqrt(a - b)*log(-2*(a^2 - 2*a*b + b^2)*cos(2*x)^ 
2 - 2*a^2 + b^2 + 2*((a - b)*cos(2*x)^2 - (2*a - b)*cos(2*x) + a)*sqrt(a - 
 b)*sqrt(((a - b)*cos(2*x) - a - b)/(cos(2*x) - 1)) + 4*(a^2 - a*b)*cos(2* 
x)) - 4*((a - 4*b)*cos(2*x) - a + 2*b)*sqrt(((a - b)*cos(2*x) - a - b)/(co 
s(2*x) - 1)))/(b*cos(2*x) - b), -1/6*(3*(b*cos(2*x) - b)*sqrt(-a + b)*arct 
an(-sqrt(-a + b)*sqrt(((a - b)*cos(2*x) - a - b)/(cos(2*x) - 1))*(cos(2*x) 
 - 1)/((a - b)*cos(2*x) - a)) + 2*((a - 4*b)*cos(2*x) - a + 2*b)*sqrt(((a 
- b)*cos(2*x) - a - b)/(cos(2*x) - 1)))/(b*cos(2*x) - b)]
 

Sympy [F]

\[ \int \cot ^3(x) \sqrt {a+b \cot ^2(x)} \, dx=\int \sqrt {a + b \cot ^{2}{\left (x \right )}} \cot ^{3}{\left (x \right )}\, dx \] Input:

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

Output:

Integral(sqrt(a + b*cot(x)**2)*cot(x)**3, x)
 

Maxima [F(-2)]

Exception generated. \[ \int \cot ^3(x) \sqrt {a+b \cot ^2(x)} \, dx=\text {Exception raised: ValueError} \] Input:

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

Output:

Exception raised: ValueError >> Computation failed since Maxima requested 
additional constraints; using the 'assume' command before evaluation *may* 
 help (example of legal syntax is 'assume(4*a-4*b>0)', see `assume?` for m 
ore detail
 

Giac [B] (verification not implemented)

Leaf count of result is larger than twice the leaf count of optimal. 198 vs. \(2 (54) = 108\).

Time = 0.50 (sec) , antiderivative size = 198, normalized size of antiderivative = 3.00 \[ \int \cot ^3(x) \sqrt {a+b \cot ^2(x)} \, dx=\frac {1}{6} \, {\left (3 \, \sqrt {a - b} \log \left ({\left (\sqrt {a - b} \sin \left (x\right ) - \sqrt {a \sin \left (x\right )^{2} - b \sin \left (x\right )^{2} + b}\right )}^{2}\right ) + \frac {4 \, {\left (3 \, {\left (\sqrt {a - b} \sin \left (x\right ) - \sqrt {a \sin \left (x\right )^{2} - b \sin \left (x\right )^{2} + b}\right )}^{4} \sqrt {a - b} {\left (a - 2 \, b\right )} + 6 \, {\left (\sqrt {a - b} \sin \left (x\right ) - \sqrt {a \sin \left (x\right )^{2} - b \sin \left (x\right )^{2} + b}\right )}^{2} \sqrt {a - b} b^{2} + {\left (a b^{2} - 4 \, b^{3}\right )} \sqrt {a - b}\right )}}{{\left ({\left (\sqrt {a - b} \sin \left (x\right ) - \sqrt {a \sin \left (x\right )^{2} - b \sin \left (x\right )^{2} + b}\right )}^{2} - b\right )}^{3}}\right )} \mathrm {sgn}\left (\sin \left (x\right )\right ) \] Input:

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

Output:

1/6*(3*sqrt(a - b)*log((sqrt(a - b)*sin(x) - sqrt(a*sin(x)^2 - b*sin(x)^2 
+ b))^2) + 4*(3*(sqrt(a - b)*sin(x) - sqrt(a*sin(x)^2 - b*sin(x)^2 + b))^4 
*sqrt(a - b)*(a - 2*b) + 6*(sqrt(a - b)*sin(x) - sqrt(a*sin(x)^2 - b*sin(x 
)^2 + b))^2*sqrt(a - b)*b^2 + (a*b^2 - 4*b^3)*sqrt(a - b))/((sqrt(a - b)*s 
in(x) - sqrt(a*sin(x)^2 - b*sin(x)^2 + b))^2 - b)^3)*sgn(sin(x))
 

Mupad [B] (verification not implemented)

Time = 12.18 (sec) , antiderivative size = 66, normalized size of antiderivative = 1.00 \[ \int \cot ^3(x) \sqrt {a+b \cot ^2(x)} \, dx=\sqrt {b\,{\mathrm {cot}\left (x\right )}^2+a}-\frac {{\left (b\,{\mathrm {cot}\left (x\right )}^2+a\right )}^{3/2}}{3\,b}+2\,\mathrm {atan}\left (\frac {2\,\sqrt {b\,{\mathrm {cot}\left (x\right )}^2+a}\,\sqrt {\frac {b}{4}-\frac {a}{4}}}{a-b}\right )\,\sqrt {\frac {b}{4}-\frac {a}{4}} \] Input:

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

Output:

(a + b*cot(x)^2)^(1/2) - (a + b*cot(x)^2)^(3/2)/(3*b) + 2*atan((2*(a + b*c 
ot(x)^2)^(1/2)*(b/4 - a/4)^(1/2))/(a - b))*(b/4 - a/4)^(1/2)
 

Reduce [F]

\[ \int \cot ^3(x) \sqrt {a+b \cot ^2(x)} \, dx=\frac {-\sqrt {\cot \left (x \right )^{2} b +a}\, \cot \left (x \right )^{2} b +2 \sqrt {\cot \left (x \right )^{2} b +a}\, a +3 \left (\int \frac {\sqrt {\cot \left (x \right )^{2} b +a}\, \cot \left (x \right )^{3}}{\cot \left (x \right )^{2} b +a}d x \right ) a b -3 \left (\int \frac {\sqrt {\cot \left (x \right )^{2} b +a}\, \cot \left (x \right )^{3}}{\cot \left (x \right )^{2} b +a}d x \right ) b^{2}}{3 b} \] Input:

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

Output:

( - sqrt(cot(x)**2*b + a)*cot(x)**2*b + 2*sqrt(cot(x)**2*b + a)*a + 3*int( 
(sqrt(cot(x)**2*b + a)*cot(x)**3)/(cot(x)**2*b + a),x)*a*b - 3*int((sqrt(c 
ot(x)**2*b + a)*cot(x)**3)/(cot(x)**2*b + a),x)*b**2)/(3*b)