Internal problem ID [9893]
Internal file name [OUTPUT/8840_Monday_June_06_2022_05_36_24_AM_63446099/index.tex]
Book: Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section: Chapter 4, linear fourth order
Problem number: 1571.
ODE order: 4.
ODE degree: 1.
The type(s) of ODE detected by this program : "unknown"
Maple gives the following as the ode type
[[_high_order, _with_linear_symmetries]]
Unable to solve or complete the solution.
\[ \boxed {\nu ^{4} x^{4} y^{\prime \prime \prime \prime }+\left (4 \nu -2\right ) \nu ^{3} x^{3} y^{\prime \prime \prime }+\left (\nu -1\right ) \left (2 \nu -1\right ) \nu ^{2} x^{2} y^{\prime \prime }-\frac {b^{4} x^{\frac {2}{\nu }} y}{16}=0} \] Unable to solve this ODE.
\[ \begin {array}{lll} & {} & \textrm {Let's solve}\hspace {3pt} \\ {} & {} & \nu ^{4} x^{4} \left (\frac {d}{d x}\frac {d}{d x}y^{\prime \prime }\right )+\left (4 \nu -2\right ) \nu ^{3} x^{3} \left (\frac {d}{d x}y^{\prime \prime }\right )+\left (\nu -1\right ) \left (2 \nu -1\right ) \nu ^{2} x^{2} \left (\frac {d}{d x}y^{\prime }\right )-\frac {b^{4} x^{\frac {2}{\nu }} y}{16}=0 \\ \bullet & {} & \textrm {Highest derivative means the order of the ODE is}\hspace {3pt} 4 \\ {} & {} & \frac {d}{d x}\frac {d}{d x}y^{\prime \prime } \end {array} \]
Maple trace
`Methods for high order ODEs: --- Trying classification methods --- trying a quadrature checking if the LODE has constant coefficients checking if the LODE is of Euler type trying high order exact linear fully integrable trying to convert to a linear ODE with constant coefficients trying differential order: 4; missing the dependent variable Equation is the LCLM of 1/4/nu^2*b^2*x^(-2+floor(1/nu))*y(x)+diff(diff(y(x),x),x), -1/4/nu^2*b^2*x^(-2+floor(1/nu))*y(x)+diff(diff(y trying a symmetry of the form [xi=0, eta=F(x)] checking if the LODE is missing y -> Trying an equivalence, under non-integer power transformations, to LODEs admitting Liouvillian solutions. -> Trying a Liouvillian solution using Kovacics algorithm <- No Liouvillian solutions exists -> Trying a solution in terms of special functions: -> Bessel <- Bessel successful <- special function solution successful trying a symmetry of the form [xi=0, eta=F(x)] checking if the LODE is missing y -> Trying an equivalence, under non-integer power transformations, to LODEs admitting Liouvillian solutions. -> Trying a Liouvillian solution using Kovacics algorithm <- No Liouvillian solutions exists -> Trying a solution in terms of special functions: -> Bessel <- Bessel successful <- special function solution successful <- solving the LCLM ode successful `
✓ Solution by Maple
Time used: 0.578 (sec). Leaf size: 143
dsolve(nu^4*x^4*diff(diff(diff(diff(y(x),x),x),x),x)+(4*nu-2)*nu^3*x^3*diff(diff(diff(y(x),x),x),x)+(nu-1)*(2*nu-1)*nu^2*x^2*diff(diff(y(x),x),x)-1/16*b^4*x^(2/nu)*y(x)=0,y(x), singsol=all)
\[ y \left (x \right ) = \sqrt {x}\, \left (\operatorname {BesselY}\left (\frac {1}{{\lfloor \frac {1}{\nu }\rfloor }}, \frac {\sqrt {\frac {b^{2}}{\nu ^{2}}}\, x^{\frac {{\lfloor \frac {1}{\nu }\rfloor }}{2}}}{{\lfloor \frac {1}{\nu }\rfloor }}\right ) c_{2} +\operatorname {BesselJ}\left (\frac {1}{{\lfloor \frac {1}{\nu }\rfloor }}, \frac {\sqrt {\frac {b^{2}}{\nu ^{2}}}\, x^{\frac {{\lfloor \frac {1}{\nu }\rfloor }}{2}}}{{\lfloor \frac {1}{\nu }\rfloor }}\right ) c_{1} +\operatorname {BesselY}\left (\frac {1}{{\lfloor \frac {1}{\nu }\rfloor }}, \frac {\sqrt {-\frac {b^{2}}{\nu ^{2}}}\, x^{\frac {{\lfloor \frac {1}{\nu }\rfloor }}{2}}}{{\lfloor \frac {1}{\nu }\rfloor }}\right ) c_{4} +\operatorname {BesselJ}\left (\frac {1}{{\lfloor \frac {1}{\nu }\rfloor }}, \frac {\sqrt {-\frac {b^{2}}{\nu ^{2}}}\, x^{\frac {{\lfloor \frac {1}{\nu }\rfloor }}{2}}}{{\lfloor \frac {1}{\nu }\rfloor }}\right ) c_{3} \right ) \]
✓ Solution by Mathematica
Time used: 0.069 (sec). Leaf size: 195
DSolve[-1/16*(b^4*x^(2/\[Nu])*y[x]) + (-1 + \[Nu])*\[Nu]^2*(-1 + 2*\[Nu])*x^2*y''[x] + \[Nu]^3*(-2 + 4*\[Nu])*x^3*y'''[x] + \[Nu]^4*x^4*y''''[x] == 0,y[x],x,IncludeSingularSolutions -> True]
\[ y(x)\to 8^{-\nu -1} b^{\nu } \left (x^{2/\nu }\right )^{\nu /4} \left (4^{\nu } (4 c_1 \operatorname {Gamma}(1-\nu )-i c_2 \operatorname {Gamma}(2-\nu )) \operatorname {BesselJ}\left (-\nu ,b \sqrt [4]{x^{2/\nu }}\right )+4^{\nu } (4 c_1 \operatorname {Gamma}(1-\nu )+i c_2 \operatorname {Gamma}(2-\nu )) \operatorname {BesselI}\left (-\nu ,b \sqrt [4]{x^{2/\nu }}\right )+i^{\nu } \left ((4 c_3 \operatorname {Gamma}(\nu +1)-i c_4 \operatorname {Gamma}(\nu +2)) \operatorname {BesselJ}\left (\nu ,b \sqrt [4]{x^{2/\nu }}\right )+(4 c_3 \operatorname {Gamma}(\nu +1)+i c_4 \operatorname {Gamma}(\nu +2)) \operatorname {BesselI}\left (\nu ,b \sqrt [4]{x^{2/\nu }}\right )\right )\right ) \]