33.3 problem 965

33.3.1 Maple step by step solution

Internal problem ID [4198]
Internal file name [OUTPUT/3691_Sunday_June_05_2022_10_13_22_AM_25934494/index.tex]

Book: Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section: Various 33
Problem number: 965.
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]

Unable to solve or complete the solution.

\[ \boxed {x y {y^{\prime }}^{2}+\left (a +x^{2}-y^{2}\right ) y^{\prime }-y x=0} \] 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 {-a -x^{2}+y^{2}+\sqrt {y^{4}+2 y^{2} x^{2}+x^{4}-2 y^{2} a +2 a \,x^{2}+a^{2}}}{2 y x} \tag {1} \\ y^{\prime }&=-\frac {-y^{2}+x^{2}+\sqrt {y^{4}+2 y^{2} x^{2}+x^{4}-2 y^{2} a +2 a \,x^{2}+a^{2}}+a}{2 y x} \tag {2} \end {align*}

Now each one of the above ODE is solved.

Solving equation (1)

Writing the ode as \begin {align*} y^{\prime }&=\frac {-a -x^{2}+y^{2}+\sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}}{2 y x}\\ y^{\prime }&= \omega \left ( x,y\right ) \end {align*}

The condition of Lie symmetry is the linearized PDE given by \begin {align*} \eta _{x}+\omega \left ( \eta _{y}-\xi _{x}\right ) -\omega ^{2}\xi _{y}-\omega _{x}\xi -\omega _{y}\eta =0\tag {A} \end {align*}

The type of this ode is not in the lookup table. To determine \(\xi ,\eta \) then (A) is solved using ansatz. Making bivariate polynomials of degree 3 to use as anstaz gives \begin{align*} \tag{1E} \xi &= x^{3} a_{7}+x^{2} y a_{8}+x \,y^{2} a_{9}+y^{3} a_{10}+x^{2} a_{4}+x y a_{5}+y^{2} a_{6}+x a_{2}+y a_{3}+a_{1} \\ \tag{2E} \eta &= x^{3} b_{7}+x^{2} y b_{8}+x \,y^{2} b_{9}+y^{3} b_{10}+x^{2} b_{4}+x y b_{5}+y^{2} b_{6}+x b_{2}+y b_{3}+b_{1} \\ \end{align*} Where the unknown coefficients are \[ \{a_{1}, a_{2}, a_{3}, a_{4}, a_{5}, a_{6}, a_{7}, a_{8}, a_{9}, a_{10}, b_{1}, b_{2}, b_{3}, b_{4}, b_{5}, b_{6}, b_{7}, b_{8}, b_{9}, b_{10}\} \] Substituting equations (1E,2E) and \(\omega \) into (A) gives \begin{equation} \tag{5E} 3 x^{2} b_{7}+2 x y b_{8}+y^{2} b_{9}+2 x b_{4}+y b_{5}+b_{2}+\frac {\left (-a -x^{2}+y^{2}+\sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}\right ) \left (-3 x^{2} a_{7}+x^{2} b_{8}-2 x y a_{8}+2 x y b_{9}-y^{2} a_{9}+3 y^{2} b_{10}-2 x a_{4}+x b_{5}-y a_{5}+2 y b_{6}-a_{2}+b_{3}\right )}{2 y x}-\frac {\left (-a -x^{2}+y^{2}+\sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}\right )^{2} \left (x^{2} a_{8}+2 x y a_{9}+3 y^{2} a_{10}+x a_{5}+2 y a_{6}+a_{3}\right )}{4 y^{2} x^{2}}-\left (-\frac {-a -x^{2}+y^{2}+\sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}}{2 y \,x^{2}}+\frac {-2 x +\frac {4 x^{3}+4 x \,y^{2}+4 a x}{2 \sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}}}{2 y x}\right ) \left (x^{3} a_{7}+x^{2} y a_{8}+x \,y^{2} a_{9}+y^{3} a_{10}+x^{2} a_{4}+x y a_{5}+y^{2} a_{6}+x a_{2}+y a_{3}+a_{1}\right )-\left (-\frac {-a -x^{2}+y^{2}+\sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}}{2 y^{2} x}+\frac {2 y +\frac {4 x^{2} y +4 y^{3}-4 a y}{2 \sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}}}{2 y x}\right ) \left (x^{3} b_{7}+x^{2} y b_{8}+x \,y^{2} b_{9}+y^{3} b_{10}+x^{2} b_{4}+x y b_{5}+y^{2} b_{6}+x b_{2}+y b_{3}+b_{1}\right ) = 0 \end{equation} Putting the above in normal form gives \[ \text {Expression too large to display} \] Setting the numerator to zero gives \begin{equation} \tag{6E} \text {Expression too large to display} \end{equation} Simplifying the above gives \begin{equation} \tag{6E} \text {Expression too large to display} \end{equation} Since the PDE has radicals, simplifying gives \[ \text {Expression too large to display} \] Looking at the above PDE shows the following are all the terms with \(\{x, y\}\) in them. \[ \left \{x, y, \sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}\right \} \] The following substitution is now made to be able to collect on all terms with \(\{x, y\}\) in them \[ \left \{x = v_{1}, y = v_{2}, \sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}} = v_{3}\right \} \] The above PDE (6E) now becomes \begin{equation} \tag{7E} \text {Expression too large to display} \end{equation} Collecting the above on the terms \(v_i\) introduced, and these are \[ \{v_{1}, v_{2}, v_{3}\} \] Equation (7E) now becomes \begin{equation} \tag{8E} \text {Expression too large to display} \end{equation} Setting each coefficients in (8E) to zero gives the following equations to solve \begin {align*} -2 a_{6}&=0\\ -4 a_{10}&=0\\ 10 a a_{10}&=0\\ 14 a a_{10}&=0\\ -2 a^{2} a_{3}&=0\\ 2 a^{3} a_{3}&=0\\ -2 a_{4}-4 a_{6}&=0\\ -2 a_{5}-2 b_{4}&=0\\ -2 a_{5}+2 b_{6}&=0\\ -2 a_{5}+6 b_{6}&=0\\ 2 a_{5}+2 b_{4}&=0\\ -2 a_{8}-2 b_{7}&=0\\ 2 a_{8}+2 b_{7}&=0\\ -4 a_{9}+4 b_{10}&=0\\ -8 a_{4}+2 a_{6}+4 b_{5}&=0\\ -6 a_{4}+4 a_{6}+4 b_{5}&=0\\ -2 a_{4}+2 a_{6}+4 b_{5}&=0\\ 6 a_{4}-4 a_{6}-4 b_{5}&=0\\ -6 a_{5}-2 b_{4}+8 b_{6}&=0\\ 4 a_{5}+6 b_{4}-6 b_{6}&=0\\ -4 a_{7}+12 b_{10}-8 a_{9}&=0\\ 8 a_{7}-4 b_{8}-4 a_{9}&=0\\ -4 a_{8}+2 a_{10}+6 b_{9}&=0\\ -4 a_{8}+2 b_{9}-6 a_{10}&=0\\ 4 b_{8}+4 a_{9}-8 a_{7}&=0\\ 6 b_{9}+6 a_{10}-4 a_{8}&=0\\ 8 b_{10}+4 b_{8}-12 a_{7}&=0\\ -4 a_{7}+4 a_{9}-8 b_{10}+8 b_{8}&=0\\ 6 a_{8}-6 b_{9}-6 a_{10}+10 b_{7}&=0\\ -2 b_{7}+8 b_{9}-10 a_{8}+4 a_{10}&=0\\ 6 a a_{6}+2 a_{1}&=0\\ 8 a a_{6}+2 a_{1}&=0\\ -10 a^{2} a_{6}-4 a a_{1}&=0\\ -4 a^{2} a_{6}-2 a a_{1}&=0\\ 4 a^{3} a_{6}+2 a^{2} a_{1}&=0\\ -16 a^{2} a_{10}+2 a a_{3}&=0\\ -6 a^{2} a_{10}+2 a a_{3}&=0\\ 6 a^{3} a_{10}-4 a^{2} a_{3}&=0\\ -2 a^{2} a_{5}-2 a b_{1}&=0\\ 2 a^{3} a_{5}+2 a^{2} b_{1}&=0\\ -8 a a_{5}+12 a b_{6}&=0\\ -6 a^{2} a_{5}+6 a^{2} b_{6}&=0\\ -4 a^{2} a_{9}-4 a b_{3}&=0\\ 4 a^{3} a_{9}+4 a^{2} b_{3}&=0\\ 8 a a_{9}-8 a b_{10}&=0\\ 12 a a_{9}-12 a b_{10}&=0\\ -2 a^{2} a_{8}-4 a a_{3}-2 a b_{2}&=0\\ 2 a^{3} a_{8}+6 a^{2} a_{3}+2 a^{2} b_{2}&=0\\ 4 a a_{4}-8 a a_{6}-4 a b_{5}&=0\\ -2 a^{2} a_{4}+12 a^{2} a_{6}+4 a^{2} b_{5}&=0\\ -4 a a_{5}-2 a b_{4}-2 b_{1}&=0\\ 6 a a_{5}+4 a b_{4}+2 b_{1}&=0\\ 6 a^{2} a_{5}+2 a^{2} b_{4}+4 a b_{1}&=0\\ 4 a a_{5}-6 a b_{6}-2 b_{1}&=0\\ 6 a a_{5}-8 a b_{6}-2 b_{1}&=0\\ -12 a a_{8}+18 a a_{10}+12 a b_{9}&=0\\ -12 a^{2} a_{9}+8 a^{2} b_{10}-4 a b_{3}&=0\\ -8 a a_{4}+12 a a_{6}+8 a b_{5}-2 a_{1}&=0\\ 2 a a_{4}-8 a a_{6}-4 a b_{5}+2 a_{1}&=0\\ -8 a^{2} a_{8}+18 a^{2} a_{10}+6 a^{2} b_{9}-4 a a_{3}&=0\\ -4 a a_{8}-2 a b_{7}-2 a_{3}-2 b_{2}&=0\\ 6 a a_{8}+4 a b_{7}+2 a_{3}+2 b_{2}&=0\\ 6 a^{2} a_{8}+2 a^{2} b_{7}+6 a a_{3}+4 a b_{2}&=0\\ -12 a a_{7}+12 a a_{9}+8 a b_{8}-4 a_{2}+4 b_{3}&=0\\ 4 a a_{7}-8 a a_{9}-4 a b_{8}+4 a_{2}-4 b_{3}&=0\\ -4 a^{2} a_{7}+12 a^{2} a_{9}+4 a^{2} b_{8}-4 a a_{2}+8 a b_{3}&=0\\ 6 a a_{8}-12 a a_{10}-6 a b_{9}+2 a_{3}+2 b_{2}&=0\\ 10 a a_{8}-12 a a_{10}-8 a b_{9}-2 a_{3}-2 b_{2}&=0\\ 8 a a_{7}-12 a a_{9}-4 a b_{8}+16 a b_{10}-4 a_{2}+4 b_{3}&=0 \end {align*}

Solving the above equations for the unknowns gives \begin {align*} a_{1}&=0\\ a_{2}&=a b_{10}\\ a_{3}&=0\\ a_{4}&=0\\ a_{5}&=0\\ a_{6}&=0\\ a_{7}&=b_{10}\\ a_{8}&=0\\ a_{9}&=b_{10}\\ a_{10}&=0\\ b_{1}&=0\\ b_{2}&=0\\ b_{3}&=-a b_{10}\\ b_{4}&=0\\ b_{5}&=0\\ b_{6}&=0\\ b_{7}&=0\\ b_{8}&=b_{10}\\ b_{9}&=0\\ b_{10}&=b_{10} \end {align*}

Substituting the above solution in the anstaz (1E,2E) (using \(1\) as arbitrary value for any unknown in the RHS) gives \begin{align*} \xi &= x^{3}+x \,y^{2}+a x \\ \eta &= x^{2} y +y^{3}-a y \\ \end{align*} The next step is to determine the canonical coordinates \(R,S\). The canonical coordinates map \(\left ( x,y\right ) \to \left ( R,S \right )\) where \(\left ( R,S \right )\) are the canonical coordinates which make the original ode become a quadrature and hence solved by integration.

The characteristic pde which is used to find the canonical coordinates is \begin {align*} \frac {d x}{\xi } &= \frac {d y}{\eta } = dS \tag {1} \end {align*}

The above comes from the requirements that \(\left ( \xi \frac {\partial }{\partial x} + \eta \frac {\partial }{\partial y}\right ) S(x,y) = 1\). Starting with the first pair of ode’s in (1) gives an ode to solve for the independent variable \(R\) in the canonical coordinates, where \(S(R)\). Therefore \begin {align*} \frac {dy}{dx} &= \frac {\eta }{\xi }\\ &= \frac {x^{2} y +y^{3}-a y}{x^{3}+x \,y^{2}+a x}\\ &= -\frac {y \left (-x^{2}-y^{2}+a \right )}{x \left (x^{2}+y^{2}+a \right )} \end {align*}

This is easily solved to give \begin {align*} \frac {1}{\frac {1}{y^{2}}+\frac {1}{x^{2}+a}} = -\frac {x \sqrt {x^{2}+a}}{\sqrt {c_{1} -\frac {4 a}{x^{2}+a}}}+\frac {x^{2}}{2}+\frac {a}{2} \end {align*}

Where now the coordinate \(R\) is taken as the constant of integration. Hence \begin {align*} R &= \frac {4 x^{4}+8 x^{2} y^{2}+4 y^{4}+8 a \,x^{2}-8 y^{2} a +4 a^{2}}{x^{4}-2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}} \end {align*}

Since \(\xi \) depends on \(y\) and \(\eta \) depends on \(x\) then we can use either one to find \(S\). Let us use \begin {align*} dS &= \frac {dx}{\xi } \\ &= \frac {dx}{x^{3}+x \,y^{2}+a x} \end {align*}

But we have now to replace \(y\) in \(\xi \) from its value from the solution of \(\frac {dy}{dx}=\frac {\eta }{\xi }\) found above. This results in \begin {align*} \xi &= x^{3}+x {\left (-\frac {x \sqrt {x^{2}+a}}{\sqrt {c_{1} -\frac {4 a}{x^{2}+a}}}+\frac {x^{2}}{2}+\frac {a}{2}\right )}^{2}+a x \end {align*}

Integrating gives \begin {align*} S &= \frac {dx}{x^{3}+x {\left (-\frac {x \sqrt {x^{2}+a}}{\sqrt {c_{1} -\frac {4 a}{x^{2}+a}}}+\frac {x^{2}}{2}+\frac {a}{2}\right )}^{2}+a x}\\ &= \text {Expression too large to display} \end {align*}

Where the constant of integration is set to zero as we just need one solution. Replacing back \(c_{1} = \frac {4 x^{4}+8 x^{2} y^{2}+4 y^{4}+8 a \,x^{2}-8 y^{2} a +4 a^{2}}{x^{4}-2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}\) then the above becomes \begin {align*} S &= \text {Expression too large to display} \end {align*}

Unable to determine ODE type.

Solving equation (2)

Writing the ode as \begin {align*} y^{\prime }&=-\frac {-y^{2}+x^{2}+\sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}+a}{2 y x}\\ y^{\prime }&= \omega \left ( x,y\right ) \end {align*}

The condition of Lie symmetry is the linearized PDE given by \begin {align*} \eta _{x}+\omega \left ( \eta _{y}-\xi _{x}\right ) -\omega ^{2}\xi _{y}-\omega _{x}\xi -\omega _{y}\eta =0\tag {A} \end {align*}

The type of this ode is not in the lookup table. To determine \(\xi ,\eta \) then (A) is solved using ansatz. Making bivariate polynomials of degree 3 to use as anstaz gives \begin{align*} \tag{1E} \xi &= x^{3} a_{7}+x^{2} y a_{8}+x \,y^{2} a_{9}+y^{3} a_{10}+x^{2} a_{4}+x y a_{5}+y^{2} a_{6}+x a_{2}+y a_{3}+a_{1} \\ \tag{2E} \eta &= x^{3} b_{7}+x^{2} y b_{8}+x \,y^{2} b_{9}+y^{3} b_{10}+x^{2} b_{4}+x y b_{5}+y^{2} b_{6}+x b_{2}+y b_{3}+b_{1} \\ \end{align*} Where the unknown coefficients are \[ \{a_{1}, a_{2}, a_{3}, a_{4}, a_{5}, a_{6}, a_{7}, a_{8}, a_{9}, a_{10}, b_{1}, b_{2}, b_{3}, b_{4}, b_{5}, b_{6}, b_{7}, b_{8}, b_{9}, b_{10}\} \] Substituting equations (1E,2E) and \(\omega \) into (A) gives \begin{equation} \tag{5E} 3 x^{2} b_{7}+2 x y b_{8}+y^{2} b_{9}+2 x b_{4}+y b_{5}+b_{2}-\frac {\left (-y^{2}+x^{2}+\sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}+a \right ) \left (-3 x^{2} a_{7}+x^{2} b_{8}-2 x y a_{8}+2 x y b_{9}-y^{2} a_{9}+3 y^{2} b_{10}-2 x a_{4}+x b_{5}-y a_{5}+2 y b_{6}-a_{2}+b_{3}\right )}{2 y x}-\frac {\left (-y^{2}+x^{2}+\sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}+a \right )^{2} \left (x^{2} a_{8}+2 x y a_{9}+3 y^{2} a_{10}+x a_{5}+2 y a_{6}+a_{3}\right )}{4 y^{2} x^{2}}-\left (-\frac {2 x +\frac {4 x^{3}+4 x \,y^{2}+4 a x}{2 \sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}}}{2 y x}+\frac {-y^{2}+x^{2}+\sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}+a}{2 x^{2} y}\right ) \left (x^{3} a_{7}+x^{2} y a_{8}+x \,y^{2} a_{9}+y^{3} a_{10}+x^{2} a_{4}+x y a_{5}+y^{2} a_{6}+x a_{2}+y a_{3}+a_{1}\right )-\left (-\frac {-2 y +\frac {4 x^{2} y +4 y^{3}-4 a y}{2 \sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}}}{2 y x}+\frac {-y^{2}+x^{2}+\sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}+a}{2 y^{2} x}\right ) \left (x^{3} b_{7}+x^{2} y b_{8}+x \,y^{2} b_{9}+y^{3} b_{10}+x^{2} b_{4}+x y b_{5}+y^{2} b_{6}+x b_{2}+y b_{3}+b_{1}\right ) = 0 \end{equation} Putting the above in normal form gives \[ \text {Expression too large to display} \] Setting the numerator to zero gives \begin{equation} \tag{6E} \text {Expression too large to display} \end{equation} Simplifying the above gives \begin{equation} \tag{6E} \text {Expression too large to display} \end{equation} Since the PDE has radicals, simplifying gives \[ \text {Expression too large to display} \] Looking at the above PDE shows the following are all the terms with \(\{x, y\}\) in them. \[ \left \{x, y, \sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}}\right \} \] The following substitution is now made to be able to collect on all terms with \(\{x, y\}\) in them \[ \left \{x = v_{1}, y = v_{2}, \sqrt {x^{4}+2 x^{2} y^{2}+y^{4}+2 a \,x^{2}-2 y^{2} a +a^{2}} = v_{3}\right \} \] The above PDE (6E) now becomes \begin{equation} \tag{7E} \text {Expression too large to display} \end{equation} Collecting the above on the terms \(v_i\) introduced, and these are \[ \{v_{1}, v_{2}, v_{3}\} \] Equation (7E) now becomes \begin{equation} \tag{8E} \text {Expression too large to display} \end{equation} Setting each coefficients in (8E) to zero gives the following equations to solve \begin {align*} -2 a_{6}&=0\\ 2 a_{6}&=0\\ -4 a_{10}&=0\\ 4 a_{10}&=0\\ -14 a a_{10}&=0\\ 10 a a_{10}&=0\\ -2 a^{2} a_{3}&=0\\ -2 a^{3} a_{3}&=0\\ 2 a_{4}+4 a_{6}&=0\\ -2 a_{5}-2 b_{4}&=0\\ -2 a_{5}+2 b_{6}&=0\\ 2 a_{5}-6 b_{6}&=0\\ 2 a_{5}-2 b_{6}&=0\\ -4 a_{9}+4 b_{10}&=0\\ -2 b_{7}-2 a_{8}&=0\\ -4 b_{10}+4 a_{9}&=0\\ -2 a_{4}+2 a_{6}+4 b_{5}&=0\\ 6 a_{4}-4 a_{6}-4 b_{5}&=0\\ 8 a_{4}-2 a_{6}-4 b_{5}&=0\\ 4 a_{5}+6 b_{4}-6 b_{6}&=0\\ 6 a_{5}+2 b_{4}-8 b_{6}&=0\\ 8 a_{7}-4 b_{8}-4 a_{9}&=0\\ 12 a_{7}-4 b_{8}-8 b_{10}&=0\\ 4 a_{8}-6 b_{9}-6 a_{10}&=0\\ 8 a_{9}-12 b_{10}+4 a_{7}&=0\\ 6 a_{10}-2 b_{9}+4 a_{8}&=0\\ 6 b_{9}-4 a_{8}+2 a_{10}&=0\\ 10 a_{8}-4 a_{10}+2 b_{7}-8 b_{9}&=0\\ 10 b_{7}+6 a_{8}-6 b_{9}-6 a_{10}&=0\\ 8 b_{8}-4 a_{7}+4 a_{9}-8 b_{10}&=0\\ -8 a a_{6}-2 a_{1}&=0\\ 6 a a_{6}+2 a_{1}&=0\\ -4 a^{2} a_{6}-2 a a_{1}&=0\\ 10 a^{2} a_{6}+4 a a_{1}&=0\\ -4 a^{3} a_{6}-2 a^{2} a_{1}&=0\\ -6 a^{2} a_{10}+2 a a_{3}&=0\\ 16 a^{2} a_{10}-2 a a_{3}&=0\\ -6 a^{3} a_{10}+4 a^{2} a_{3}&=0\\ -2 a^{2} a_{5}-2 a b_{1}&=0\\ -2 a^{3} a_{5}-2 a^{2} b_{1}&=0\\ 8 a a_{5}-12 a b_{6}&=0\\ 6 a^{2} a_{5}-6 a^{2} b_{6}&=0\\ -4 a^{2} a_{9}-4 a b_{3}&=0\\ -4 a^{3} a_{9}-4 a^{2} b_{3}&=0\\ -12 a a_{9}+12 a b_{10}&=0\\ 8 a a_{9}-8 a b_{10}&=0\\ -2 a^{2} a_{8}-4 a a_{3}-2 a b_{2}&=0\\ -2 a^{3} a_{8}-6 a^{2} a_{3}-2 a^{2} b_{2}&=0\\ -4 a a_{4}+8 a a_{6}+4 a b_{5}&=0\\ 2 a^{2} a_{4}-12 a^{2} a_{6}-4 a^{2} b_{5}&=0\\ -6 a a_{5}-4 a b_{4}-2 b_{1}&=0\\ -4 a a_{5}-2 a b_{4}-2 b_{1}&=0\\ -6 a^{2} a_{5}-2 a^{2} b_{4}-4 a b_{1}&=0\\ -6 a a_{5}+8 a b_{6}+2 b_{1}&=0\\ 4 a a_{5}-6 a b_{6}-2 b_{1}&=0\\ 12 a a_{8}-18 a a_{10}-12 a b_{9}&=0\\ 12 a^{2} a_{9}-8 a^{2} b_{10}+4 a b_{3}&=0\\ 2 a a_{4}-8 a a_{6}-4 a b_{5}+2 a_{1}&=0\\ 8 a a_{4}-12 a a_{6}-8 a b_{5}+2 a_{1}&=0\\ 8 a^{2} a_{8}-18 a^{2} a_{10}-6 a^{2} b_{9}+4 a a_{3}&=0\\ -6 a a_{8}-4 a b_{7}-2 a_{3}-2 b_{2}&=0\\ -4 a a_{8}-2 a b_{7}-2 a_{3}-2 b_{2}&=0\\ -6 a^{2} a_{8}-2 a^{2} b_{7}-6 a a_{3}-4 a b_{2}&=0\\ 4 a a_{7}-8 a a_{9}-4 a b_{8}+4 a_{2}-4 b_{3}&=0\\ 12 a a_{7}-12 a a_{9}-8 a b_{8}+4 a_{2}-4 b_{3}&=0\\ 4 a^{2} a_{7}-12 a^{2} a_{9}-4 a^{2} b_{8}+4 a a_{2}-8 a b_{3}&=0\\ -10 a a_{8}+12 a a_{10}+8 a b_{9}+2 a_{3}+2 b_{2}&=0\\ 6 a a_{8}-12 a a_{10}-6 a b_{9}+2 a_{3}+2 b_{2}&=0\\ -8 a a_{7}+12 a a_{9}+4 a b_{8}-16 a b_{10}+4 a_{2}-4 b_{3}&=0 \end {align*}

Solving the above equations for the unknowns gives \begin {align*} a_{1}&=0\\ a_{2}&=a b_{10}\\ a_{3}&=0\\ a_{4}&=0\\ a_{5}&=0\\ a_{6}&=0\\ a_{7}&=b_{10}\\ a_{8}&=0\\ a_{9}&=b_{10}\\ a_{10}&=0\\ b_{1}&=0\\ b_{2}&=0\\ b_{3}&=-a b_{10}\\ b_{4}&=0\\ b_{5}&=0\\ b_{6}&=0\\ b_{7}&=0\\ b_{8}&=b_{10}\\ b_{9}&=0\\ b_{10}&=b_{10} \end {align*}

Substituting the above solution in the anstaz (1E,2E) (using \(1\) as arbitrary value for any unknown in the RHS) gives \begin{align*} \xi &= x^{3}+x \,y^{2}+a x \\ \eta &= x^{2} y +y^{3}-a y \\ \end{align*} The next step is to determine the canonical coordinates \(R,S\). The canonical coordinates map \(\left ( x,y\right ) \to \left ( R,S \right )\) where \(\left ( R,S \right )\) are the canonical coordinates which make the original ode become a quadrature and hence solved by integration.

The characteristic pde which is used to find the canonical coordinates is \begin {align*} \frac {d x}{\xi } &= \frac {d y}{\eta } = dS \tag {1} \end {align*}

The above comes from the requirements that \(\left ( \xi \frac {\partial }{\partial x} + \eta \frac {\partial }{\partial y}\right ) S(x,y) = 1\). Starting with the first pair of ode’s in (1) gives an ode to solve for the independent variable \(R\) in the canonical coordinates, where \(S(R)\). Unable to determine \(R\). Terminating

Unable to determine ODE type.

33.3.1 Maple step by step solution

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

Solution by Maple

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

\[ \text {No solution found} \]

Solution by Mathematica

Time used: 0.419 (sec). Leaf size: 112

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

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