Integrand size = 35, antiderivative size = 134 \[ \int \frac {\left (-4 b+a x^4\right ) \left (b+a x^4\right )^{3/4}}{x^8 \left (4 b+a x^4\right )} \, dx=\frac {\left (6 b-a x^4\right ) \left (b+a x^4\right )^{3/4}}{42 b x^7}+\frac {3^{3/4} a^{7/4} \arctan \left (\frac {\sqrt [4]{3} \sqrt [4]{a} x}{\sqrt {2} \sqrt [4]{b+a x^4}}\right )}{8 \sqrt {2} b}+\frac {3^{3/4} a^{7/4} \text {arctanh}\left (\frac {\sqrt [4]{3} \sqrt [4]{a} x}{\sqrt {2} \sqrt [4]{b+a x^4}}\right )}{8 \sqrt {2} b} \]
1/42*(-a*x^4+6*b)*(a*x^4+b)^(3/4)/b/x^7+1/16*3^(3/4)*a^(7/4)*arctan(1/2*3^ (1/4)*a^(1/4)*x*2^(1/2)/(a*x^4+b)^(1/4))*2^(1/2)/b+1/16*3^(3/4)*a^(7/4)*ar ctanh(1/2*3^(1/4)*a^(1/4)*x*2^(1/2)/(a*x^4+b)^(1/4))*2^(1/2)/b
Time = 0.63 (sec) , antiderivative size = 134, normalized size of antiderivative = 1.00 \[ \int \frac {\left (-4 b+a x^4\right ) \left (b+a x^4\right )^{3/4}}{x^8 \left (4 b+a x^4\right )} \, dx=\frac {\left (6 b-a x^4\right ) \left (b+a x^4\right )^{3/4}}{42 b x^7}+\frac {3^{3/4} a^{7/4} \arctan \left (\frac {\sqrt [4]{3} \sqrt [4]{a} x}{\sqrt {2} \sqrt [4]{b+a x^4}}\right )}{8 \sqrt {2} b}+\frac {3^{3/4} a^{7/4} \text {arctanh}\left (\frac {\sqrt [4]{3} \sqrt [4]{a} x}{\sqrt {2} \sqrt [4]{b+a x^4}}\right )}{8 \sqrt {2} b} \]
((6*b - a*x^4)*(b + a*x^4)^(3/4))/(42*b*x^7) + (3^(3/4)*a^(7/4)*ArcTan[(3^ (1/4)*a^(1/4)*x)/(Sqrt[2]*(b + a*x^4)^(1/4))])/(8*Sqrt[2]*b) + (3^(3/4)*a^ (7/4)*ArcTanh[(3^(1/4)*a^(1/4)*x)/(Sqrt[2]*(b + a*x^4)^(1/4))])/(8*Sqrt[2] *b)
Time = 0.33 (sec) , antiderivative size = 154, normalized size of antiderivative = 1.15, number of steps used = 9, number of rules used = 8, \(\frac {\text {number of rules}}{\text {integrand size}}\) = 0.229, Rules used = {1050, 27, 1053, 27, 902, 756, 216, 219}
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.
| \(\displaystyle \int \frac {\left (a x^4-4 b\right ) \left (a x^4+b\right )^{3/4}}{x^8 \left (a x^4+4 b\right )} \, dx\) |
| \(\Big \downarrow \) 1050 |
| \(\displaystyle \frac {\int \frac {4 a b \left (11 a x^4+2 b\right )}{x^4 \sqrt [4]{a x^4+b} \left (a x^4+4 b\right )}dx}{28 b}+\frac {\left (a x^4+b\right )^{3/4}}{7 x^7}\) |
| \(\Big \downarrow \) 27 |
| \(\displaystyle \frac {1}{7} a \int \frac {11 a x^4+2 b}{x^4 \sqrt [4]{a x^4+b} \left (a x^4+4 b\right )}dx+\frac {\left (a x^4+b\right )^{3/4}}{7 x^7}\) |
| \(\Big \downarrow \) 1053 |
| \(\displaystyle \frac {1}{7} a \left (-\frac {\int -\frac {126 a b^2}{\sqrt [4]{a x^4+b} \left (a x^4+4 b\right )}dx}{12 b^2}-\frac {\left (a x^4+b\right )^{3/4}}{6 b x^3}\right )+\frac {\left (a x^4+b\right )^{3/4}}{7 x^7}\) |
| \(\Big \downarrow \) 27 |
| \(\displaystyle \frac {1}{7} a \left (\frac {21}{2} a \int \frac {1}{\sqrt [4]{a x^4+b} \left (a x^4+4 b\right )}dx-\frac {\left (a x^4+b\right )^{3/4}}{6 b x^3}\right )+\frac {\left (a x^4+b\right )^{3/4}}{7 x^7}\) |
| \(\Big \downarrow \) 902 |
| \(\displaystyle \frac {1}{7} a \left (\frac {21}{2} a \int \frac {1}{4 b-\frac {3 a b x^4}{a x^4+b}}d\frac {x}{\sqrt [4]{a x^4+b}}-\frac {\left (a x^4+b\right )^{3/4}}{6 b x^3}\right )+\frac {\left (a x^4+b\right )^{3/4}}{7 x^7}\) |
| \(\Big \downarrow \) 756 |
| \(\displaystyle \frac {1}{7} a \left (\frac {21}{2} a \left (\frac {\int \frac {1}{2-\frac {\sqrt {3} \sqrt {a} x^2}{\sqrt {a x^4+b}}}d\frac {x}{\sqrt [4]{a x^4+b}}}{4 b}+\frac {\int \frac {1}{\frac {\sqrt {3} \sqrt {a} x^2}{\sqrt {a x^4+b}}+2}d\frac {x}{\sqrt [4]{a x^4+b}}}{4 b}\right )-\frac {\left (a x^4+b\right )^{3/4}}{6 b x^3}\right )+\frac {\left (a x^4+b\right )^{3/4}}{7 x^7}\) |
| \(\Big \downarrow \) 216 |
| \(\displaystyle \frac {1}{7} a \left (\frac {21}{2} a \left (\frac {\int \frac {1}{2-\frac {\sqrt {3} \sqrt {a} x^2}{\sqrt {a x^4+b}}}d\frac {x}{\sqrt [4]{a x^4+b}}}{4 b}+\frac {\arctan \left (\frac {\sqrt [4]{3} \sqrt [4]{a} x}{\sqrt {2} \sqrt [4]{a x^4+b}}\right )}{4 \sqrt {2} \sqrt [4]{3} \sqrt [4]{a} b}\right )-\frac {\left (a x^4+b\right )^{3/4}}{6 b x^3}\right )+\frac {\left (a x^4+b\right )^{3/4}}{7 x^7}\) |
| \(\Big \downarrow \) 219 |
| \(\displaystyle \frac {1}{7} a \left (\frac {21}{2} a \left (\frac {\arctan \left (\frac {\sqrt [4]{3} \sqrt [4]{a} x}{\sqrt {2} \sqrt [4]{a x^4+b}}\right )}{4 \sqrt {2} \sqrt [4]{3} \sqrt [4]{a} b}+\frac {\text {arctanh}\left (\frac {\sqrt [4]{3} \sqrt [4]{a} x}{\sqrt {2} \sqrt [4]{a x^4+b}}\right )}{4 \sqrt {2} \sqrt [4]{3} \sqrt [4]{a} b}\right )-\frac {\left (a x^4+b\right )^{3/4}}{6 b x^3}\right )+\frac {\left (a x^4+b\right )^{3/4}}{7 x^7}\) |
(b + a*x^4)^(3/4)/(7*x^7) + (a*(-1/6*(b + a*x^4)^(3/4)/(b*x^3) + (21*a*(Ar cTan[(3^(1/4)*a^(1/4)*x)/(Sqrt[2]*(b + a*x^4)^(1/4))]/(4*Sqrt[2]*3^(1/4)*a ^(1/4)*b) + ArcTanh[(3^(1/4)*a^(1/4)*x)/(Sqrt[2]*(b + a*x^4)^(1/4))]/(4*Sq rt[2]*3^(1/4)*a^(1/4)*b)))/2))/7
3.20.30.3.1 Defintions of rubi rules used
Int[(a_)*(Fx_), x_Symbol] :> Simp[a Int[Fx, x], x] /; FreeQ[a, x] && !Ma tchQ[Fx, (b_)*(Gx_) /; FreeQ[b, x]]
Int[((a_) + (b_.)*(x_)^2)^(-1), x_Symbol] :> Simp[(1/(Rt[a, 2]*Rt[b, 2]))*A rcTan[Rt[b, 2]*(x/Rt[a, 2])], x] /; FreeQ[{a, b}, x] && PosQ[a/b] && (GtQ[a , 0] || GtQ[b, 0])
Int[((a_) + (b_.)*(x_)^2)^(-1), x_Symbol] :> Simp[(1/(Rt[a, 2]*Rt[-b, 2]))* ArcTanh[Rt[-b, 2]*(x/Rt[a, 2])], x] /; FreeQ[{a, b}, x] && NegQ[a/b] && (Gt Q[a, 0] || LtQ[b, 0])
Int[((a_) + (b_.)*(x_)^4)^(-1), x_Symbol] :> With[{r = Numerator[Rt[-a/b, 2 ]], s = Denominator[Rt[-a/b, 2]]}, Simp[r/(2*a) Int[1/(r - s*x^2), x], x] + Simp[r/(2*a) Int[1/(r + s*x^2), x], x]] /; FreeQ[{a, b}, x] && !GtQ[a /b, 0]
Int[((a_) + (b_.)*(x_)^(n_))^(p_)/((c_) + (d_.)*(x_)^(n_)), x_Symbol] :> Su bst[Int[1/(c - (b*c - a*d)*x^n), x], x, x/(a + b*x^n)^(1/n)] /; FreeQ[{a, b , c, d}, x] && NeQ[b*c - a*d, 0] && EqQ[n*p + 1, 0] && IntegerQ[n]
Int[((g_.)*(x_))^(m_)*((a_) + (b_.)*(x_)^(n_))^(p_.)*((c_) + (d_.)*(x_)^(n_ ))^(q_.)*((e_) + (f_.)*(x_)^(n_)), x_Symbol] :> Simp[e*(g*x)^(m + 1)*(a + b *x^n)^(p + 1)*((c + d*x^n)^q/(a*g*(m + 1))), x] - Simp[1/(a*g^n*(m + 1)) Int[(g*x)^(m + n)*(a + b*x^n)^p*(c + d*x^n)^(q - 1)*Simp[c*(b*e - a*f)*(m + 1) + e*n*(b*c*(p + 1) + a*d*q) + d*((b*e - a*f)*(m + 1) + b*e*n*(p + q + 1 ))*x^n, x], x], x] /; FreeQ[{a, b, c, d, e, f, g, p}, x] && IGtQ[n, 0] && G tQ[q, 0] && LtQ[m, -1] && !(EqQ[q, 1] && SimplerQ[e + f*x^n, c + d*x^n])
Int[((g_.)*(x_))^(m_)*((a_) + (b_.)*(x_)^(n_))^(p_.)*((c_) + (d_.)*(x_)^(n_ ))^(q_.)*((e_) + (f_.)*(x_)^(n_)), x_Symbol] :> Simp[e*(g*x)^(m + 1)*(a + b *x^n)^(p + 1)*((c + d*x^n)^(q + 1)/(a*c*g*(m + 1))), x] + Simp[1/(a*c*g^n*( m + 1)) Int[(g*x)^(m + n)*(a + b*x^n)^p*(c + d*x^n)^q*Simp[a*f*c*(m + 1) - e*(b*c + a*d)*(m + n + 1) - e*n*(b*c*p + a*d*q) - b*e*d*(m + n*(p + q + 2 ) + 1)*x^n, x], x], x] /; FreeQ[{a, b, c, d, e, f, g, p, q}, x] && IGtQ[n, 0] && LtQ[m, -1]
Time = 0.69 (sec) , antiderivative size = 151, normalized size of antiderivative = 1.13
| method | result | size |
| pseudoelliptic | \(-\frac {\left (126 \arctan \left (\frac {3^{\frac {3}{4}} \sqrt {2}\, \left (a \,x^{4}+b \right )^{\frac {1}{4}}}{3 a^{\frac {1}{4}} x}\right ) a^{2} \sqrt {2}\, x^{7}-63 \ln \left (\frac {\sqrt {2}\, 3^{\frac {1}{4}} a^{\frac {1}{4}} x +2 \left (a \,x^{4}+b \right )^{\frac {1}{4}}}{-\sqrt {2}\, 3^{\frac {1}{4}} a^{\frac {1}{4}} x +2 \left (a \,x^{4}+b \right )^{\frac {1}{4}}}\right ) a^{2} \sqrt {2}\, x^{7}+16 a^{\frac {5}{4}} \left (a \,x^{4}+b \right )^{\frac {3}{4}} x^{4} 3^{\frac {1}{4}}-96 b \left (a \,x^{4}+b \right )^{\frac {3}{4}} 3^{\frac {1}{4}} a^{\frac {1}{4}}\right ) 3^{\frac {3}{4}}}{2016 x^{7} a^{\frac {1}{4}} b}\) | \(151\) |
-1/2016*(126*arctan(1/3*3^(3/4)/a^(1/4)/x*2^(1/2)*(a*x^4+b)^(1/4))*a^2*2^( 1/2)*x^7-63*ln((2^(1/2)*3^(1/4)*a^(1/4)*x+2*(a*x^4+b)^(1/4))/(-2^(1/2)*3^( 1/4)*a^(1/4)*x+2*(a*x^4+b)^(1/4)))*a^2*2^(1/2)*x^7+16*a^(5/4)*(a*x^4+b)^(3 /4)*x^4*3^(1/4)-96*b*(a*x^4+b)^(3/4)*3^(1/4)*a^(1/4))/x^7*3^(3/4)/a^(1/4)/ b
Result contains complex when optimal does not.
Time = 55.91 (sec) , antiderivative size = 593, normalized size of antiderivative = 4.43 \[ \int \frac {\left (-4 b+a x^4\right ) \left (b+a x^4\right )^{3/4}}{x^8 \left (4 b+a x^4\right )} \, dx=\frac {21 \, \left (\frac {27}{4}\right )^{\frac {1}{4}} \left (\frac {a^{7}}{b^{4}}\right )^{\frac {1}{4}} b x^{7} \log \left (\frac {18 \, \sqrt {3} {\left (a x^{4} + b\right )}^{\frac {1}{4}} \sqrt {\frac {a^{7}}{b^{4}}} a^{2} b^{2} x^{3} + 8 \, \left (\frac {27}{4}\right )^{\frac {3}{4}} \sqrt {a x^{4} + b} \left (\frac {a^{7}}{b^{4}}\right )^{\frac {3}{4}} b^{3} x^{2} + 36 \, {\left (a x^{4} + b\right )}^{\frac {3}{4}} a^{5} x + 3 \, \left (\frac {27}{4}\right )^{\frac {1}{4}} {\left (7 \, a^{4} b x^{4} + 4 \, a^{3} b^{2}\right )} \left (\frac {a^{7}}{b^{4}}\right )^{\frac {1}{4}}}{4 \, {\left (a x^{4} + 4 \, b\right )}}\right ) + 21 i \, \left (\frac {27}{4}\right )^{\frac {1}{4}} \left (\frac {a^{7}}{b^{4}}\right )^{\frac {1}{4}} b x^{7} \log \left (-\frac {18 \, \sqrt {3} {\left (a x^{4} + b\right )}^{\frac {1}{4}} \sqrt {\frac {a^{7}}{b^{4}}} a^{2} b^{2} x^{3} + 8 i \, \left (\frac {27}{4}\right )^{\frac {3}{4}} \sqrt {a x^{4} + b} \left (\frac {a^{7}}{b^{4}}\right )^{\frac {3}{4}} b^{3} x^{2} - 36 \, {\left (a x^{4} + b\right )}^{\frac {3}{4}} a^{5} x + 3 \, \left (\frac {27}{4}\right )^{\frac {1}{4}} {\left (-7 i \, a^{4} b x^{4} - 4 i \, a^{3} b^{2}\right )} \left (\frac {a^{7}}{b^{4}}\right )^{\frac {1}{4}}}{4 \, {\left (a x^{4} + 4 \, b\right )}}\right ) - 21 i \, \left (\frac {27}{4}\right )^{\frac {1}{4}} \left (\frac {a^{7}}{b^{4}}\right )^{\frac {1}{4}} b x^{7} \log \left (-\frac {18 \, \sqrt {3} {\left (a x^{4} + b\right )}^{\frac {1}{4}} \sqrt {\frac {a^{7}}{b^{4}}} a^{2} b^{2} x^{3} - 8 i \, \left (\frac {27}{4}\right )^{\frac {3}{4}} \sqrt {a x^{4} + b} \left (\frac {a^{7}}{b^{4}}\right )^{\frac {3}{4}} b^{3} x^{2} - 36 \, {\left (a x^{4} + b\right )}^{\frac {3}{4}} a^{5} x + 3 \, \left (\frac {27}{4}\right )^{\frac {1}{4}} {\left (7 i \, a^{4} b x^{4} + 4 i \, a^{3} b^{2}\right )} \left (\frac {a^{7}}{b^{4}}\right )^{\frac {1}{4}}}{4 \, {\left (a x^{4} + 4 \, b\right )}}\right ) - 21 \, \left (\frac {27}{4}\right )^{\frac {1}{4}} \left (\frac {a^{7}}{b^{4}}\right )^{\frac {1}{4}} b x^{7} \log \left (\frac {18 \, \sqrt {3} {\left (a x^{4} + b\right )}^{\frac {1}{4}} \sqrt {\frac {a^{7}}{b^{4}}} a^{2} b^{2} x^{3} - 8 \, \left (\frac {27}{4}\right )^{\frac {3}{4}} \sqrt {a x^{4} + b} \left (\frac {a^{7}}{b^{4}}\right )^{\frac {3}{4}} b^{3} x^{2} + 36 \, {\left (a x^{4} + b\right )}^{\frac {3}{4}} a^{5} x - 3 \, \left (\frac {27}{4}\right )^{\frac {1}{4}} {\left (7 \, a^{4} b x^{4} + 4 \, a^{3} b^{2}\right )} \left (\frac {a^{7}}{b^{4}}\right )^{\frac {1}{4}}}{4 \, {\left (a x^{4} + 4 \, b\right )}}\right ) - 16 \, {\left (a x^{4} + b\right )}^{\frac {3}{4}} {\left (a x^{4} - 6 \, b\right )}}{672 \, b x^{7}} \]
1/672*(21*(27/4)^(1/4)*(a^7/b^4)^(1/4)*b*x^7*log(1/4*(18*sqrt(3)*(a*x^4 + b)^(1/4)*sqrt(a^7/b^4)*a^2*b^2*x^3 + 8*(27/4)^(3/4)*sqrt(a*x^4 + b)*(a^7/b ^4)^(3/4)*b^3*x^2 + 36*(a*x^4 + b)^(3/4)*a^5*x + 3*(27/4)^(1/4)*(7*a^4*b*x ^4 + 4*a^3*b^2)*(a^7/b^4)^(1/4))/(a*x^4 + 4*b)) + 21*I*(27/4)^(1/4)*(a^7/b ^4)^(1/4)*b*x^7*log(-1/4*(18*sqrt(3)*(a*x^4 + b)^(1/4)*sqrt(a^7/b^4)*a^2*b ^2*x^3 + 8*I*(27/4)^(3/4)*sqrt(a*x^4 + b)*(a^7/b^4)^(3/4)*b^3*x^2 - 36*(a* x^4 + b)^(3/4)*a^5*x + 3*(27/4)^(1/4)*(-7*I*a^4*b*x^4 - 4*I*a^3*b^2)*(a^7/ b^4)^(1/4))/(a*x^4 + 4*b)) - 21*I*(27/4)^(1/4)*(a^7/b^4)^(1/4)*b*x^7*log(- 1/4*(18*sqrt(3)*(a*x^4 + b)^(1/4)*sqrt(a^7/b^4)*a^2*b^2*x^3 - 8*I*(27/4)^( 3/4)*sqrt(a*x^4 + b)*(a^7/b^4)^(3/4)*b^3*x^2 - 36*(a*x^4 + b)^(3/4)*a^5*x + 3*(27/4)^(1/4)*(7*I*a^4*b*x^4 + 4*I*a^3*b^2)*(a^7/b^4)^(1/4))/(a*x^4 + 4 *b)) - 21*(27/4)^(1/4)*(a^7/b^4)^(1/4)*b*x^7*log(1/4*(18*sqrt(3)*(a*x^4 + b)^(1/4)*sqrt(a^7/b^4)*a^2*b^2*x^3 - 8*(27/4)^(3/4)*sqrt(a*x^4 + b)*(a^7/b ^4)^(3/4)*b^3*x^2 + 36*(a*x^4 + b)^(3/4)*a^5*x - 3*(27/4)^(1/4)*(7*a^4*b*x ^4 + 4*a^3*b^2)*(a^7/b^4)^(1/4))/(a*x^4 + 4*b)) - 16*(a*x^4 + b)^(3/4)*(a* x^4 - 6*b))/(b*x^7)
\[ \int \frac {\left (-4 b+a x^4\right ) \left (b+a x^4\right )^{3/4}}{x^8 \left (4 b+a x^4\right )} \, dx=\int \frac {\left (a x^{4} - 4 b\right ) \left (a x^{4} + b\right )^{\frac {3}{4}}}{x^{8} \left (a x^{4} + 4 b\right )}\, dx \]
\[ \int \frac {\left (-4 b+a x^4\right ) \left (b+a x^4\right )^{3/4}}{x^8 \left (4 b+a x^4\right )} \, dx=\int { \frac {{\left (a x^{4} + b\right )}^{\frac {3}{4}} {\left (a x^{4} - 4 \, b\right )}}{{\left (a x^{4} + 4 \, b\right )} x^{8}} \,d x } \]
\[ \int \frac {\left (-4 b+a x^4\right ) \left (b+a x^4\right )^{3/4}}{x^8 \left (4 b+a x^4\right )} \, dx=\int { \frac {{\left (a x^{4} + b\right )}^{\frac {3}{4}} {\left (a x^{4} - 4 \, b\right )}}{{\left (a x^{4} + 4 \, b\right )} x^{8}} \,d x } \]
Timed out. \[ \int \frac {\left (-4 b+a x^4\right ) \left (b+a x^4\right )^{3/4}}{x^8 \left (4 b+a x^4\right )} \, dx=\int -\frac {{\left (a\,x^4+b\right )}^{3/4}\,\left (4\,b-a\,x^4\right )}{x^8\,\left (a\,x^4+4\,b\right )} \,d x \]