15.20.2 problem 2

Internal problem ID [3310]
Book : Differential Equations by Alfred L. Nelson, Karl W. Folley, Max Coral. 3rd ed. DC heath. Boston. 1964
Section : Exercise 38, page 173
Problem number : 2
Date solved : Monday, January 27, 2025 at 07:33:07 AM
CAS classification : [[_homogeneous, `class C`], _dAlembert]

\begin{align*} x&=y-{y^{\prime }}^{3} \end{align*}

Solution by Maple

Time used: 0.034 (sec). Leaf size: 211

dsolve(x=y(x)-diff(y(x),x)^3,y(x), singsol=all)
 
\begin{align*} x -\frac {3 \left (-x +y \left (x \right )\right )^{{2}/{3}}}{2}-3 \left (-x +y \left (x \right )\right )^{{1}/{3}}-3 \ln \left (\left (-x +y \left (x \right )\right )^{{1}/{3}}-1\right )-c_{1} &= 0 \\ x +\frac {3 \left (-x +y \left (x \right )\right )^{{2}/{3}}}{4}-\frac {3 i \sqrt {3}\, \left (-x +y \left (x \right )\right )^{{2}/{3}}}{4}+\frac {3 \left (-x +y \left (x \right )\right )^{{1}/{3}}}{2}+\frac {3 i \sqrt {3}\, \left (-x +y \left (x \right )\right )^{{1}/{3}}}{2}+6 \ln \left (2\right )-3 \ln \left (-2 i \sqrt {3}\, \left (-x +y \left (x \right )\right )^{{1}/{3}}-2 \left (-x +y \left (x \right )\right )^{{1}/{3}}-4\right )-c_{1} &= 0 \\ x +\frac {3 \left (-x +y \left (x \right )\right )^{{2}/{3}}}{4}+\frac {3 i \sqrt {3}\, \left (-x +y \left (x \right )\right )^{{2}/{3}}}{4}+\frac {3 \left (-x +y \left (x \right )\right )^{{1}/{3}}}{2}-\frac {3 i \sqrt {3}\, \left (-x +y \left (x \right )\right )^{{1}/{3}}}{2}+6 \ln \left (2\right )-3 \ln \left (2 i \sqrt {3}\, \left (-x +y \left (x \right )\right )^{{1}/{3}}-2 \left (-x +y \left (x \right )\right )^{{1}/{3}}-4\right )-c_{1} &= 0 \\ \end{align*}

Solution by Mathematica

Time used: 9.004 (sec). Leaf size: 271

DSolve[x==y[x]-D[y[x],x]^3,y[x],x,IncludeSingularSolutions -> True]
 
\begin{align*} \text {Solve}\left [\frac {3}{2} (y(x)-x)^{2/3}+3 \sqrt [3]{y(x)-x}+3 \log \left (\sqrt [3]{y(x)-x}-1\right )-x&=c_1,y(x)\right ] \\ \text {Solve}\left [\frac {1}{4} i \left (-12 i \arctan \left (\frac {2 \sqrt [3]{y(x)-x}+1}{\sqrt {3}}\right )-3 i \left (\sqrt {3}-i\right ) (y(x)-x)^{2/3}+6 i \left (\sqrt {3}+i\right ) \sqrt [3]{y(x)-x}+6 \log \left ((y(x)-x)^{2/3}+\sqrt [3]{y(x)-x}+1\right )-4 x\right )&=c_1,y(x)\right ] \\ \text {Solve}\left [\frac {y(x)}{2}+\frac {1}{4} \left (2 (x-y(x))+\frac {3}{2} \left (1-i \sqrt {3}\right ) (y(x)-x)^{2/3}+3 \left (1+i \sqrt {3}\right ) \sqrt [3]{y(x)-x}-6 \log \left (2 i \sqrt [3]{y(x)-x}+\sqrt {2+2 i \sqrt {3}}\right )\right )&=c_1,y(x)\right ] \\ \end{align*}