3.10 \(\int \frac{1}{\sqrt{b \tan ^3(e+f x)}} \, dx\)

Optimal. Leaf size=255 \[ \frac{\tan ^{-1}\left (1-\sqrt{2} \sqrt{\tan (e+f x)}\right ) \tan ^{\frac{3}{2}}(e+f x)}{\sqrt{2} f \sqrt{b \tan ^3(e+f x)}}-\frac{\tan ^{-1}\left (\sqrt{2} \sqrt{\tan (e+f x)}+1\right ) \tan ^{\frac{3}{2}}(e+f x)}{\sqrt{2} f \sqrt{b \tan ^3(e+f x)}}-\frac{2 \tan (e+f x)}{f \sqrt{b \tan ^3(e+f x)}}-\frac{\tan ^{\frac{3}{2}}(e+f x) \log \left (\tan (e+f x)-\sqrt{2} \sqrt{\tan (e+f x)}+1\right )}{2 \sqrt{2} f \sqrt{b \tan ^3(e+f x)}}+\frac{\tan ^{\frac{3}{2}}(e+f x) \log \left (\tan (e+f x)+\sqrt{2} \sqrt{\tan (e+f x)}+1\right )}{2 \sqrt{2} f \sqrt{b \tan ^3(e+f x)}} \]

[Out]

(-2*Tan[e + f*x])/(f*Sqrt[b*Tan[e + f*x]^3]) + (ArcTan[1 - Sqrt[2]*Sqrt[Tan[e + f*x]]]*Tan[e + f*x]^(3/2))/(Sq
rt[2]*f*Sqrt[b*Tan[e + f*x]^3]) - (ArcTan[1 + Sqrt[2]*Sqrt[Tan[e + f*x]]]*Tan[e + f*x]^(3/2))/(Sqrt[2]*f*Sqrt[
b*Tan[e + f*x]^3]) - (Log[1 - Sqrt[2]*Sqrt[Tan[e + f*x]] + Tan[e + f*x]]*Tan[e + f*x]^(3/2))/(2*Sqrt[2]*f*Sqrt
[b*Tan[e + f*x]^3]) + (Log[1 + Sqrt[2]*Sqrt[Tan[e + f*x]] + Tan[e + f*x]]*Tan[e + f*x]^(3/2))/(2*Sqrt[2]*f*Sqr
t[b*Tan[e + f*x]^3])

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Rubi [A]  time = 0.114648, antiderivative size = 255, normalized size of antiderivative = 1., number of steps used = 13, number of rules used = 10, integrand size = 14, \(\frac{\text{number of rules}}{\text{integrand size}}\) = 0.714, Rules used = {3658, 3474, 3476, 329, 297, 1162, 617, 204, 1165, 628} \[ \frac{\tan ^{-1}\left (1-\sqrt{2} \sqrt{\tan (e+f x)}\right ) \tan ^{\frac{3}{2}}(e+f x)}{\sqrt{2} f \sqrt{b \tan ^3(e+f x)}}-\frac{\tan ^{-1}\left (\sqrt{2} \sqrt{\tan (e+f x)}+1\right ) \tan ^{\frac{3}{2}}(e+f x)}{\sqrt{2} f \sqrt{b \tan ^3(e+f x)}}-\frac{2 \tan (e+f x)}{f \sqrt{b \tan ^3(e+f x)}}-\frac{\tan ^{\frac{3}{2}}(e+f x) \log \left (\tan (e+f x)-\sqrt{2} \sqrt{\tan (e+f x)}+1\right )}{2 \sqrt{2} f \sqrt{b \tan ^3(e+f x)}}+\frac{\tan ^{\frac{3}{2}}(e+f x) \log \left (\tan (e+f x)+\sqrt{2} \sqrt{\tan (e+f x)}+1\right )}{2 \sqrt{2} f \sqrt{b \tan ^3(e+f x)}} \]

Antiderivative was successfully verified.

[In]

Int[1/Sqrt[b*Tan[e + f*x]^3],x]

[Out]

(-2*Tan[e + f*x])/(f*Sqrt[b*Tan[e + f*x]^3]) + (ArcTan[1 - Sqrt[2]*Sqrt[Tan[e + f*x]]]*Tan[e + f*x]^(3/2))/(Sq
rt[2]*f*Sqrt[b*Tan[e + f*x]^3]) - (ArcTan[1 + Sqrt[2]*Sqrt[Tan[e + f*x]]]*Tan[e + f*x]^(3/2))/(Sqrt[2]*f*Sqrt[
b*Tan[e + f*x]^3]) - (Log[1 - Sqrt[2]*Sqrt[Tan[e + f*x]] + Tan[e + f*x]]*Tan[e + f*x]^(3/2))/(2*Sqrt[2]*f*Sqrt
[b*Tan[e + f*x]^3]) + (Log[1 + Sqrt[2]*Sqrt[Tan[e + f*x]] + Tan[e + f*x]]*Tan[e + f*x]^(3/2))/(2*Sqrt[2]*f*Sqr
t[b*Tan[e + f*x]^3])

Rule 3658

Int[(u_.)*((b_.)*tan[(e_.) + (f_.)*(x_)]^(n_))^(p_), x_Symbol] :> With[{ff = FreeFactors[Tan[e + f*x], x]}, Di
st[((b*ff^n)^IntPart[p]*(b*Tan[e + f*x]^n)^FracPart[p])/(Tan[e + f*x]/ff)^(n*FracPart[p]), Int[ActivateTrig[u]
*(Tan[e + f*x]/ff)^(n*p), x], x]] /; FreeQ[{b, e, f, n, p}, x] &&  !IntegerQ[p] && IntegerQ[n] && (EqQ[u, 1] |
| MatchQ[u, ((d_.)*(trig_)[e + f*x])^(m_.) /; FreeQ[{d, m}, x] && MemberQ[{sin, cos, tan, cot, sec, csc}, trig
]])

Rule 3474

Int[((b_.)*tan[(c_.) + (d_.)*(x_)])^(n_), x_Symbol] :> Simp[(b*Tan[c + d*x])^(n + 1)/(b*d*(n + 1)), x] - Dist[
1/b^2, Int[(b*Tan[c + d*x])^(n + 2), x], x] /; FreeQ[{b, c, d}, x] && LtQ[n, -1]

Rule 3476

Int[((b_.)*tan[(c_.) + (d_.)*(x_)])^(n_), x_Symbol] :> Dist[b/d, Subst[Int[x^n/(b^2 + x^2), x], x, b*Tan[c + d
*x]], x] /; FreeQ[{b, c, d, n}, x] &&  !IntegerQ[n]

Rule 329

Int[((c_.)*(x_))^(m_)*((a_) + (b_.)*(x_)^(n_))^(p_), x_Symbol] :> With[{k = Denominator[m]}, Dist[k/c, Subst[I
nt[x^(k*(m + 1) - 1)*(a + (b*x^(k*n))/c^n)^p, x], x, (c*x)^(1/k)], x]] /; FreeQ[{a, b, c, p}, x] && IGtQ[n, 0]
 && FractionQ[m] && IntBinomialQ[a, b, c, n, m, p, x]

Rule 297

Int[(x_)^2/((a_) + (b_.)*(x_)^4), x_Symbol] :> With[{r = Numerator[Rt[a/b, 2]], s = Denominator[Rt[a/b, 2]]},
Dist[1/(2*s), Int[(r + s*x^2)/(a + b*x^4), x], x] - Dist[1/(2*s), Int[(r - s*x^2)/(a + b*x^4), x], x]] /; Free
Q[{a, b}, x] && (GtQ[a/b, 0] || (PosQ[a/b] && AtomQ[SplitProduct[SumBaseQ, a]] && AtomQ[SplitProduct[SumBaseQ,
 b]]))

Rule 1162

Int[((d_) + (e_.)*(x_)^2)/((a_) + (c_.)*(x_)^4), x_Symbol] :> With[{q = Rt[(2*d)/e, 2]}, Dist[e/(2*c), Int[1/S
imp[d/e + q*x + x^2, x], x], x] + Dist[e/(2*c), Int[1/Simp[d/e - q*x + x^2, x], x], x]] /; FreeQ[{a, c, d, e},
 x] && EqQ[c*d^2 - a*e^2, 0] && PosQ[d*e]

Rule 617

Int[((a_) + (b_.)*(x_) + (c_.)*(x_)^2)^(-1), x_Symbol] :> With[{q = 1 - 4*Simplify[(a*c)/b^2]}, Dist[-2/b, Sub
st[Int[1/(q - x^2), x], x, 1 + (2*c*x)/b], x] /; RationalQ[q] && (EqQ[q^2, 1] ||  !RationalQ[b^2 - 4*a*c])] /;
 FreeQ[{a, b, c}, x] && NeQ[b^2 - 4*a*c, 0]

Rule 204

Int[((a_) + (b_.)*(x_)^2)^(-1), x_Symbol] :> -Simp[ArcTan[(Rt[-b, 2]*x)/Rt[-a, 2]]/(Rt[-a, 2]*Rt[-b, 2]), x] /
; FreeQ[{a, b}, x] && PosQ[a/b] && (LtQ[a, 0] || LtQ[b, 0])

Rule 1165

Int[((d_) + (e_.)*(x_)^2)/((a_) + (c_.)*(x_)^4), x_Symbol] :> With[{q = Rt[(-2*d)/e, 2]}, Dist[e/(2*c*q), Int[
(q - 2*x)/Simp[d/e + q*x - x^2, x], x], x] + Dist[e/(2*c*q), Int[(q + 2*x)/Simp[d/e - q*x - x^2, x], x], x]] /
; FreeQ[{a, c, d, e}, x] && EqQ[c*d^2 - a*e^2, 0] && NegQ[d*e]

Rule 628

Int[((d_) + (e_.)*(x_))/((a_.) + (b_.)*(x_) + (c_.)*(x_)^2), x_Symbol] :> Simp[(d*Log[RemoveContent[a + b*x +
c*x^2, x]])/b, x] /; FreeQ[{a, b, c, d, e}, x] && EqQ[2*c*d - b*e, 0]

Rubi steps

\begin{align*} \int \frac{1}{\sqrt{b \tan ^3(e+f x)}} \, dx &=\frac{\tan ^{\frac{3}{2}}(e+f x) \int \frac{1}{\tan ^{\frac{3}{2}}(e+f x)} \, dx}{\sqrt{b \tan ^3(e+f x)}}\\ &=-\frac{2 \tan (e+f x)}{f \sqrt{b \tan ^3(e+f x)}}-\frac{\tan ^{\frac{3}{2}}(e+f x) \int \sqrt{\tan (e+f x)} \, dx}{\sqrt{b \tan ^3(e+f x)}}\\ &=-\frac{2 \tan (e+f x)}{f \sqrt{b \tan ^3(e+f x)}}-\frac{\tan ^{\frac{3}{2}}(e+f x) \operatorname{Subst}\left (\int \frac{\sqrt{x}}{1+x^2} \, dx,x,\tan (e+f x)\right )}{f \sqrt{b \tan ^3(e+f x)}}\\ &=-\frac{2 \tan (e+f x)}{f \sqrt{b \tan ^3(e+f x)}}-\frac{\left (2 \tan ^{\frac{3}{2}}(e+f x)\right ) \operatorname{Subst}\left (\int \frac{x^2}{1+x^4} \, dx,x,\sqrt{\tan (e+f x)}\right )}{f \sqrt{b \tan ^3(e+f x)}}\\ &=-\frac{2 \tan (e+f x)}{f \sqrt{b \tan ^3(e+f x)}}+\frac{\tan ^{\frac{3}{2}}(e+f x) \operatorname{Subst}\left (\int \frac{1-x^2}{1+x^4} \, dx,x,\sqrt{\tan (e+f x)}\right )}{f \sqrt{b \tan ^3(e+f x)}}-\frac{\tan ^{\frac{3}{2}}(e+f x) \operatorname{Subst}\left (\int \frac{1+x^2}{1+x^4} \, dx,x,\sqrt{\tan (e+f x)}\right )}{f \sqrt{b \tan ^3(e+f x)}}\\ &=-\frac{2 \tan (e+f x)}{f \sqrt{b \tan ^3(e+f x)}}-\frac{\tan ^{\frac{3}{2}}(e+f x) \operatorname{Subst}\left (\int \frac{1}{1-\sqrt{2} x+x^2} \, dx,x,\sqrt{\tan (e+f x)}\right )}{2 f \sqrt{b \tan ^3(e+f x)}}-\frac{\tan ^{\frac{3}{2}}(e+f x) \operatorname{Subst}\left (\int \frac{1}{1+\sqrt{2} x+x^2} \, dx,x,\sqrt{\tan (e+f x)}\right )}{2 f \sqrt{b \tan ^3(e+f x)}}-\frac{\tan ^{\frac{3}{2}}(e+f x) \operatorname{Subst}\left (\int \frac{\sqrt{2}+2 x}{-1-\sqrt{2} x-x^2} \, dx,x,\sqrt{\tan (e+f x)}\right )}{2 \sqrt{2} f \sqrt{b \tan ^3(e+f x)}}-\frac{\tan ^{\frac{3}{2}}(e+f x) \operatorname{Subst}\left (\int \frac{\sqrt{2}-2 x}{-1+\sqrt{2} x-x^2} \, dx,x,\sqrt{\tan (e+f x)}\right )}{2 \sqrt{2} f \sqrt{b \tan ^3(e+f x)}}\\ &=-\frac{2 \tan (e+f x)}{f \sqrt{b \tan ^3(e+f x)}}-\frac{\log \left (1-\sqrt{2} \sqrt{\tan (e+f x)}+\tan (e+f x)\right ) \tan ^{\frac{3}{2}}(e+f x)}{2 \sqrt{2} f \sqrt{b \tan ^3(e+f x)}}+\frac{\log \left (1+\sqrt{2} \sqrt{\tan (e+f x)}+\tan (e+f x)\right ) \tan ^{\frac{3}{2}}(e+f x)}{2 \sqrt{2} f \sqrt{b \tan ^3(e+f x)}}-\frac{\tan ^{\frac{3}{2}}(e+f x) \operatorname{Subst}\left (\int \frac{1}{-1-x^2} \, dx,x,1-\sqrt{2} \sqrt{\tan (e+f x)}\right )}{\sqrt{2} f \sqrt{b \tan ^3(e+f x)}}+\frac{\tan ^{\frac{3}{2}}(e+f x) \operatorname{Subst}\left (\int \frac{1}{-1-x^2} \, dx,x,1+\sqrt{2} \sqrt{\tan (e+f x)}\right )}{\sqrt{2} f \sqrt{b \tan ^3(e+f x)}}\\ &=-\frac{2 \tan (e+f x)}{f \sqrt{b \tan ^3(e+f x)}}+\frac{\tan ^{-1}\left (1-\sqrt{2} \sqrt{\tan (e+f x)}\right ) \tan ^{\frac{3}{2}}(e+f x)}{\sqrt{2} f \sqrt{b \tan ^3(e+f x)}}-\frac{\tan ^{-1}\left (1+\sqrt{2} \sqrt{\tan (e+f x)}\right ) \tan ^{\frac{3}{2}}(e+f x)}{\sqrt{2} f \sqrt{b \tan ^3(e+f x)}}-\frac{\log \left (1-\sqrt{2} \sqrt{\tan (e+f x)}+\tan (e+f x)\right ) \tan ^{\frac{3}{2}}(e+f x)}{2 \sqrt{2} f \sqrt{b \tan ^3(e+f x)}}+\frac{\log \left (1+\sqrt{2} \sqrt{\tan (e+f x)}+\tan (e+f x)\right ) \tan ^{\frac{3}{2}}(e+f x)}{2 \sqrt{2} f \sqrt{b \tan ^3(e+f x)}}\\ \end{align*}

Mathematica [C]  time = 0.0340779, size = 43, normalized size = 0.17 \[ -\frac{2 \tan (e+f x) \text{Hypergeometric2F1}\left (-\frac{1}{4},1,\frac{3}{4},-\tan ^2(e+f x)\right )}{f \sqrt{b \tan ^3(e+f x)}} \]

Antiderivative was successfully verified.

[In]

Integrate[1/Sqrt[b*Tan[e + f*x]^3],x]

[Out]

(-2*Hypergeometric2F1[-1/4, 1, 3/4, -Tan[e + f*x]^2]*Tan[e + f*x])/(f*Sqrt[b*Tan[e + f*x]^3])

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Maple [A]  time = 0.026, size = 211, normalized size = 0.8 \begin{align*} -{\frac{\tan \left ( fx+e \right ) }{4\,f} \left ( \sqrt{2}\sqrt{b\tan \left ( fx+e \right ) }\ln \left ( -{ \left ( \sqrt [4]{{b}^{2}}\sqrt{b\tan \left ( fx+e \right ) }\sqrt{2}-b\tan \left ( fx+e \right ) -\sqrt{{b}^{2}} \right ) \left ( b\tan \left ( fx+e \right ) +\sqrt [4]{{b}^{2}}\sqrt{b\tan \left ( fx+e \right ) }\sqrt{2}+\sqrt{{b}^{2}} \right ) ^{-1}} \right ) +2\,\sqrt{2}\sqrt{b\tan \left ( fx+e \right ) }\arctan \left ({\frac{\sqrt{2}\sqrt{b\tan \left ( fx+e \right ) }+\sqrt [4]{{b}^{2}}}{\sqrt [4]{{b}^{2}}}} \right ) +2\,\sqrt{2}\sqrt{b\tan \left ( fx+e \right ) }\arctan \left ({\frac{\sqrt{2}\sqrt{b\tan \left ( fx+e \right ) }-\sqrt [4]{{b}^{2}}}{\sqrt [4]{{b}^{2}}}} \right ) +8\,\sqrt [4]{{b}^{2}} \right ){\frac{1}{\sqrt{b \left ( \tan \left ( fx+e \right ) \right ) ^{3}}}}{\frac{1}{\sqrt [4]{{b}^{2}}}}} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

int(1/(b*tan(f*x+e)^3)^(1/2),x)

[Out]

-1/4/f*tan(f*x+e)*(2^(1/2)*(b*tan(f*x+e))^(1/2)*ln(-((b^2)^(1/4)*(b*tan(f*x+e))^(1/2)*2^(1/2)-b*tan(f*x+e)-(b^
2)^(1/2))/(b*tan(f*x+e)+(b^2)^(1/4)*(b*tan(f*x+e))^(1/2)*2^(1/2)+(b^2)^(1/2)))+2*2^(1/2)*(b*tan(f*x+e))^(1/2)*
arctan((2^(1/2)*(b*tan(f*x+e))^(1/2)+(b^2)^(1/4))/(b^2)^(1/4))+2*2^(1/2)*(b*tan(f*x+e))^(1/2)*arctan((2^(1/2)*
(b*tan(f*x+e))^(1/2)-(b^2)^(1/4))/(b^2)^(1/4))+8*(b^2)^(1/4))/(b*tan(f*x+e)^3)^(1/2)/(b^2)^(1/4)

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Maxima [A]  time = 1.6107, size = 170, normalized size = 0.67 \begin{align*} -\frac{\frac{2 \, \sqrt{2} \arctan \left (\frac{1}{2} \, \sqrt{2}{\left (\sqrt{2} + 2 \, \sqrt{\tan \left (f x + e\right )}\right )}\right ) + 2 \, \sqrt{2} \arctan \left (-\frac{1}{2} \, \sqrt{2}{\left (\sqrt{2} - 2 \, \sqrt{\tan \left (f x + e\right )}\right )}\right ) - \sqrt{2} \log \left (\sqrt{2} \sqrt{\tan \left (f x + e\right )} + \tan \left (f x + e\right ) + 1\right ) + \sqrt{2} \log \left (-\sqrt{2} \sqrt{\tan \left (f x + e\right )} + \tan \left (f x + e\right ) + 1\right )}{\sqrt{b}} + \frac{8}{\sqrt{b} \sqrt{\tan \left (f x + e\right )}}}{4 \, f} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(b*tan(f*x+e)^3)^(1/2),x, algorithm="maxima")

[Out]

-1/4*((2*sqrt(2)*arctan(1/2*sqrt(2)*(sqrt(2) + 2*sqrt(tan(f*x + e)))) + 2*sqrt(2)*arctan(-1/2*sqrt(2)*(sqrt(2)
 - 2*sqrt(tan(f*x + e)))) - sqrt(2)*log(sqrt(2)*sqrt(tan(f*x + e)) + tan(f*x + e) + 1) + sqrt(2)*log(-sqrt(2)*
sqrt(tan(f*x + e)) + tan(f*x + e) + 1))/sqrt(b) + 8/(sqrt(b)*sqrt(tan(f*x + e))))/f

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Fricas [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(1/(b*tan(f*x+e)^3)^(1/2),x, algorithm="fricas")

[Out]

Timed out

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Sympy [F]  time = 0., size = 0, normalized size = 0. \begin{align*} \int \frac{1}{\sqrt{b \tan ^{3}{\left (e + f x \right )}}}\, dx \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(b*tan(f*x+e)**3)**(1/2),x)

[Out]

Integral(1/sqrt(b*tan(e + f*x)**3), x)

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Giac [A]  time = 1.32153, size = 355, normalized size = 1.39 \begin{align*} -\frac{1}{4} \, b^{2}{\left (\frac{2 \, \sqrt{2}{\left | b \right |}^{\frac{3}{2}} \arctan \left (\frac{\sqrt{2}{\left (\sqrt{2} \sqrt{{\left | b \right |}} + 2 \, \sqrt{b \tan \left (f x + e\right )}\right )}}{2 \, \sqrt{{\left | b \right |}}}\right )}{b^{4} f \mathrm{sgn}\left (\tan \left (f x + e\right )\right )} + \frac{2 \, \sqrt{2}{\left | b \right |}^{\frac{3}{2}} \arctan \left (-\frac{\sqrt{2}{\left (\sqrt{2} \sqrt{{\left | b \right |}} - 2 \, \sqrt{b \tan \left (f x + e\right )}\right )}}{2 \, \sqrt{{\left | b \right |}}}\right )}{b^{4} f \mathrm{sgn}\left (\tan \left (f x + e\right )\right )} - \frac{\sqrt{2}{\left | b \right |}^{\frac{3}{2}} \log \left (b \tan \left (f x + e\right ) + \sqrt{2} \sqrt{b \tan \left (f x + e\right )} \sqrt{{\left | b \right |}} +{\left | b \right |}\right )}{b^{4} f \mathrm{sgn}\left (\tan \left (f x + e\right )\right )} + \frac{\sqrt{2}{\left | b \right |}^{\frac{3}{2}} \log \left (b \tan \left (f x + e\right ) - \sqrt{2} \sqrt{b \tan \left (f x + e\right )} \sqrt{{\left | b \right |}} +{\left | b \right |}\right )}{b^{4} f \mathrm{sgn}\left (\tan \left (f x + e\right )\right )} + \frac{8}{\sqrt{b \tan \left (f x + e\right )} b^{2} f \mathrm{sgn}\left (\tan \left (f x + e\right )\right )}\right )} \end{align*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate(1/(b*tan(f*x+e)^3)^(1/2),x, algorithm="giac")

[Out]

-1/4*b^2*(2*sqrt(2)*abs(b)^(3/2)*arctan(1/2*sqrt(2)*(sqrt(2)*sqrt(abs(b)) + 2*sqrt(b*tan(f*x + e)))/sqrt(abs(b
)))/(b^4*f*sgn(tan(f*x + e))) + 2*sqrt(2)*abs(b)^(3/2)*arctan(-1/2*sqrt(2)*(sqrt(2)*sqrt(abs(b)) - 2*sqrt(b*ta
n(f*x + e)))/sqrt(abs(b)))/(b^4*f*sgn(tan(f*x + e))) - sqrt(2)*abs(b)^(3/2)*log(b*tan(f*x + e) + sqrt(2)*sqrt(
b*tan(f*x + e))*sqrt(abs(b)) + abs(b))/(b^4*f*sgn(tan(f*x + e))) + sqrt(2)*abs(b)^(3/2)*log(b*tan(f*x + e) - s
qrt(2)*sqrt(b*tan(f*x + e))*sqrt(abs(b)) + abs(b))/(b^4*f*sgn(tan(f*x + e))) + 8/(sqrt(b*tan(f*x + e))*b^2*f*s
gn(tan(f*x + e))))