7.18 problem 19

7.18.1 Maple step by step solution

Internal problem ID [1078]
Internal file name [OUTPUT/1079_Sunday_June_05_2022_02_02_07_AM_94834817/index.tex]

Book: Elementary differential equations with boundary value problems. William F. Trench. Brooks/Cole 2001
Section: Chapter 2, First order equations. Exact equations. Integrating factors. Section 2.6 Page 91
Problem number: 19.
ODE order: 1.
ODE degree: 1.

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

Maple gives the following as the ode type

[_rational, [_Abel, `2nd type`, `class C`]]

Unable to solve or complete the solution.

\[ \boxed {3 y^{3} x^{2}-y^{2}+y+\left (-y x +2 x \right ) y^{\prime }=0} \] Unable to determine ODE type.

7.18.1 Maple step by step solution

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

Maple trace

`Methods for first order ODEs: 
--- Trying classification methods --- 
trying a quadrature 
trying 1st order linear 
trying Bernoulli 
trying separable 
trying inverse linear 
trying homogeneous types: 
trying Chini 
differential order: 1; looking for linear symmetries 
trying exact 
trying Abel 
<- Abel successful`
 

Solution by Maple

Time used: 0.015 (sec). Leaf size: 59

dsolve((3*x^2*y(x)^3-y(x)^2+y(x))+(-x*y(x)+2*x)*diff(y(x),x)=0,y(x), singsol=all)
 

\begin{align*} y \left (x \right ) &= \frac {4}{\sqrt {x}\, \sqrt {\frac {c_{1} x +48 x^{2}+4}{x}}+2} \\ y \left (x \right ) &= -\frac {4}{\sqrt {x}\, \sqrt {\frac {c_{1} x +48 x^{2}+4}{x}}-2} \\ \end{align*}

Solution by Mathematica

Time used: 0.776 (sec). Leaf size: 80

DSolve[(3*x^2*y[x]^3-y[x]^2+y[x])+(-x*y[x]+2*x)*y'[x]==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to \frac {2}{1+\sqrt {-\frac {1}{x^2}} x \sqrt {-12 x^2-4 c_1 x-1}} \\ y(x)\to \frac {2 x}{x+\frac {\sqrt {-12 x^2-4 c_1 x-1}}{\sqrt {-\frac {1}{x^2}}}} \\ y(x)\to 0 \\ \end{align*}