2.23 problem 599

2.23.1 Maple step by step solution

Internal problem ID [8933]
Internal file name [OUTPUT/7868_Monday_June_06_2022_12_48_52_AM_51719006/index.tex]

Book: Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section: Chapter 1, Additional non-linear first order
Problem number: 599.
ODE order: 1.
ODE degree: 1.

The type(s) of ODE detected by this program : "unknown"

Maple gives the following as the ode type

[[_1st_order, `_with_symmetry_[F(x),G(y)]`]]

Unable to solve or complete the solution.

\[ \boxed {y^{\prime }-\frac {-x +F \left (y^{2}+x^{2}\right )}{y}=0} \] Unable to determine ODE type.

2.23.1 Maple step by step solution

\[ \begin {array}{lll} & {} & \textrm {Let's solve}\hspace {3pt} \\ {} & {} & y^{\prime } y-F \left (y^{2}+x^{2}\right )+x =0 \\ \bullet & {} & \textrm {Highest derivative means the order of the ODE is}\hspace {3pt} 1 \\ {} & {} & y^{\prime } \\ \bullet & {} & \textrm {Solve for the highest derivative}\hspace {3pt} \\ {} & {} & y^{\prime }=\frac {-x +F \left (y^{2}+x^{2}\right )}{y} \end {array} \]

Maple trace

`Methods for first order ODEs: 
--- Trying classification methods --- 
trying homogeneous types: 
differential order: 1; looking for linear symmetries 
trying exact 
Looking for potential symmetries 
trying an equivalence to an Abel ODE 
trying 1st order ODE linearizable_by_differentiation 
--- Trying Lie symmetry methods, 1st order --- 
`, `-> Computing symmetries using: way = 3 
`, `-> Computing symmetries using: way = 4`[1, -x/y]
 

Solution by Maple

Time used: 0.031 (sec). Leaf size: 69

dsolve(diff(y(x),x) = (-x+F(y(x)^2+x^2))/y(x),y(x), singsol=all)
 

\begin{align*} y \left (x \right ) &= \operatorname {RootOf}\left (F \left (\textit {\_Z}^{2}+x^{2}\right )\right ) \\ y \left (x \right ) &= \sqrt {-x^{2}+\operatorname {RootOf}\left (-2 x +\int _{}^{\textit {\_Z}}\frac {1}{F \left (\textit {\_a} \right )}d \textit {\_a} +2 c_{1} \right )} \\ y \left (x \right ) &= -\sqrt {-x^{2}+\operatorname {RootOf}\left (-2 x +\int _{}^{\textit {\_Z}}\frac {1}{F \left (\textit {\_a} \right )}d \textit {\_a} +2 c_{1} \right )} \\ \end{align*}

Solution by Mathematica

Time used: 0.144 (sec). Leaf size: 95

DSolve[y'[x] == (-x + F[x^2 + y[x]^2])/y[x],y[x],x,IncludeSingularSolutions -> True]
 

\[ \text {Solve}\left [\int _1^{y(x)}\left (-\frac {K[2]}{F\left (x^2+K[2]^2\right )}-\int _1^x\frac {2 K[1] K[2] F'\left (K[1]^2+K[2]^2\right )}{F\left (K[1]^2+K[2]^2\right )^2}dK[1]\right )dK[2]+\int _1^x\left (1-\frac {K[1]}{F\left (K[1]^2+y(x)^2\right )}\right )dK[1]=c_1,y(x)\right ] \]