31.30 problem 931

31.30.1 Maple step by step solution

Internal problem ID [4165]
Internal file name [OUTPUT/3658_Sunday_June_05_2022_10_05_26_AM_85528302/index.tex]

Book: Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section: Various 31
Problem number: 931.
ODE order: 1.
ODE degree: 2.

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

Maple gives the following as the ode type

[_rational, [_1st_order, `_with_symmetry_[F(x),G(x)*y+H(x)]`]]

Unable to solve or complete the solution.

\[ \boxed {x \left (-x^{2}+1\right ) {y^{\prime }}^{2}-2 \left (-x^{2}+1\right ) y y^{\prime }+x \left (1-y^{2}\right )=0} \] Solving the given ode for \(y^{\prime }\) results in \(2\) differential equations to solve. Each one of these will generate a solution. The equations generated are \begin {align*} y^{\prime }&=\frac {y x^{2}+\sqrt {-x^{2} y^{2}+x^{4}+y^{2}-x^{2}}-y}{x \left (x^{2}-1\right )} \tag {1} \\ y^{\prime }&=-\frac {-y x^{2}+\sqrt {-x^{2} y^{2}+x^{4}+y^{2}-x^{2}}+y}{x \left (x^{2}-1\right )} \tag {2} \end {align*}

Now each one of the above ODE is solved.

Solving equation (1)

Unable to determine ODE type.

Unable to determine ODE type.

Solving equation (2)

Unable to determine ODE type.

Unable to determine ODE type.

31.30.1 Maple step by step solution

\[ \begin {array}{lll} & {} & \textrm {Let's solve}\hspace {3pt} \\ {} & {} & x \left (-x^{2}+1\right ) {y^{\prime }}^{2}-2 \left (-x^{2}+1\right ) y y^{\prime }+x \left (1-y^{2}\right )=0 \\ \bullet & {} & \textrm {Highest derivative means the order of the ODE is}\hspace {3pt} 1 \\ {} & {} & y^{\prime } \\ \bullet & {} & \textrm {Solve for the highest derivative}\hspace {3pt} \\ {} & {} & \left [y^{\prime }=\frac {y x^{2}+\sqrt {-x^{2} y^{2}+x^{4}+y^{2}-x^{2}}-y}{x \left (x^{2}-1\right )}, y^{\prime }=-\frac {-y x^{2}+\sqrt {-x^{2} y^{2}+x^{4}+y^{2}-x^{2}}+y}{x \left (x^{2}-1\right )}\right ] \\ \bullet & {} & \textrm {Solve the equation}\hspace {3pt} y^{\prime }=\frac {y x^{2}+\sqrt {-x^{2} y^{2}+x^{4}+y^{2}-x^{2}}-y}{x \left (x^{2}-1\right )} \\ \bullet & {} & \textrm {Solve the equation}\hspace {3pt} y^{\prime }=-\frac {-y x^{2}+\sqrt {-x^{2} y^{2}+x^{4}+y^{2}-x^{2}}+y}{x \left (x^{2}-1\right )} \\ \bullet & {} & \textrm {Set of solutions}\hspace {3pt} \\ {} & {} & \left \{\mathit {workingODE} , \mathit {workingODE}\right \} \end {array} \]

Maple trace

`Methods for first order ODEs: 
   *** Sublevel 2 *** 
   Methods for first order ODEs: 
   -> Solving 1st order ODE of high degree, 1st attempt 
   trying 1st order WeierstrassP solution for high degree ODE 
   trying 1st order WeierstrassPPrime solution for high degree ODE 
   trying 1st order JacobiSN solution for high degree ODE 
   trying 1st order ODE linearizable_by_differentiation 
   trying differential order: 1; missing variables 
   trying simple symmetries for implicit equations 
   Successful isolation of dy/dx: 2 solutions were found. Trying to solve each resulting ODE. 
      *** Sublevel 3 *** 
      Methods for first order ODEs: 
      --- Trying classification methods --- 
      trying homogeneous types: 
      trying exact 
      Looking for potential symmetries 
      trying an equivalence to an Abel ODE 
      trying 1st order ODE linearizable_by_differentiation 
      -> Calling odsolve with the ODE`, diff(diff(y(x), x), x)+(diff(y(x), x))/(x*(x^2-1)), y(x)`         *** Sublevel 4 *** 
         Methods for second order ODEs: 
         --- Trying classification methods --- 
         trying a quadrature 
         checking if the LODE has constant coefficients 
         checking if the LODE is of Euler type 
         trying a symmetry of the form [xi=0, eta=F(x)] 
         checking if the LODE is missing y 
         <- LODE missing y successful 
      <- 1st order ODE linearizable_by_differentiation successful 
   ------------------- 
   * Tackling next ODE. 
      *** Sublevel 3 *** 
      Methods for first order ODEs: 
      --- Trying classification methods --- 
      trying homogeneous types: 
      trying exact 
      Looking for potential symmetries 
      trying an equivalence to an Abel ODE 
      trying 1st order ODE linearizable_by_differentiation 
      <- 1st order ODE linearizable_by_differentiation successful`
 

Solution by Maple

Time used: 0.407 (sec). Leaf size: 33

dsolve(x*(-x^2+1)*diff(y(x),x)^2-2*(-x^2+1)*y(x)*diff(y(x),x)+x*(1-y(x)^2) = 0,y(x), singsol=all)
 

\begin{align*} y \left (x \right ) &= -x \\ y \left (x \right ) &= x \\ y \left (x \right ) &= \sqrt {-c_{1}^{2}+1}+\sqrt {x^{2}-1}\, c_{1} \\ \end{align*}

Solution by Mathematica

Time used: 0.752 (sec). Leaf size: 75

DSolve[x*(1-x^2)*(y'[x])^2-2*(1-x^2)*y[x]*y'[x]+x*(1-y[x]^2)==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to -x \cos \left (2 \tan ^{-1}\left (\sqrt {\frac {x-1}{x+1}}\right )+i c_1\right ) \\ y(x)\to -x \cos \left (2 \tan ^{-1}\left (\sqrt {\frac {x-1}{x+1}}\right )-i c_1\right ) \\ y(x)\to -x \\ y(x)\to x \\ \end{align*}