29.34.7 problem 1003

Internal problem ID [5578]
Book : Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section : Various 34
Problem number : 1003
Date solved : Monday, January 27, 2025 at 12:11:08 PM
CAS classification : [[_homogeneous, `class G`], _rational]

\begin{align*} 2 x y^{2} {y^{\prime }}^{2}-y^{3} y^{\prime }-a&=0 \end{align*}

Solution by Maple

Time used: 0.133 (sec). Leaf size: 155

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

Solution by Mathematica

Time used: 1.527 (sec). Leaf size: 151

DSolve[2 x y[x]^2 (D[y[x],x])^2 -y[x]^3 D[y[x],x] -a ==0,y[x],x,IncludeSingularSolutions -> True]
 
\begin{align*} y(x)\to -\frac {e^{-\frac {c_1}{4}} \sqrt {-8 a x+e^{c_1}}}{\sqrt {2}} \\ y(x)\to \frac {e^{-\frac {c_1}{4}} \sqrt {-8 a x+e^{c_1}}}{\sqrt {2}} \\ y(x)\to -(-2)^{3/4} \sqrt [4]{a} \sqrt [4]{x} \\ y(x)\to (-2)^{3/4} \sqrt [4]{a} \sqrt [4]{x} \\ y(x)\to (-1-i) \sqrt [4]{2} \sqrt [4]{a} \sqrt [4]{x} \\ y(x)\to (1+i) \sqrt [4]{2} \sqrt [4]{a} \sqrt [4]{x} \\ \end{align*}