34.14 problem 1016

Internal problem ID [4241]

Book: Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section: Various 34
Problem number: 1016.
ODE order: 1.
ODE degree: 3.

CAS Maple gives this as type [_quadrature]

\[ \boxed {{y^{\prime }}^{3}=a \,x^{n}} \]

Solution by Maple

Time used: 0.015 (sec). Leaf size: 100

dsolve(diff(y(x),x)^3 = a*x^n,y(x), singsol=all)
 

\begin{align*} y \left (x \right ) &= \frac {3 x \left (a \,x^{n}\right )^{\frac {1}{3}}+c_{1} \left (n +3\right )}{n +3} \\ y \left (x \right ) &= \frac {\left (3 i \sqrt {3}\, x -3 x \right ) \left (a \,x^{n}\right )^{\frac {1}{3}}+2 c_{1} \left (n +3\right )}{2 n +6} \\ y \left (x \right ) &= \frac {\left (-3 i \sqrt {3}\, x -3 x \right ) \left (a \,x^{n}\right )^{\frac {1}{3}}+2 c_{1} \left (n +3\right )}{2 n +6} \\ \end{align*}

Solution by Mathematica

Time used: 0.008 (sec). Leaf size: 95

DSolve[(y'[x])^3 ==a x^n,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to \frac {3 \sqrt [3]{a} x^{\frac {n}{3}+1}}{n+3}+c_1 \\ y(x)\to -\frac {3 \sqrt [3]{-1} \sqrt [3]{a} x^{\frac {n}{3}+1}}{n+3}+c_1 \\ y(x)\to \frac {3 (-1)^{2/3} \sqrt [3]{a} x^{\frac {n}{3}+1}}{n+3}+c_1 \\ \end{align*}