3.23 problem 4.6 (c)

Internal problem ID [13001]

Book: Ordinary Differential Equations. An introduction to the fundamentals. Kenneth B. Howell. second edition. CRC Press. FL, USA. 2020
Section: Chapter 4. SEPARABLE FIRST ORDER EQUATIONS. Additional exercises. page 90
Problem number: 4.6 (c).
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [_separable]

\[ \boxed {y y^{\prime }-x y^{2}=-9 x} \]

Solution by Maple

Time used: 0.0 (sec). Leaf size: 29

dsolve(y(x)*diff(y(x),x)=x*y(x)^2-9*x,y(x), singsol=all)
 

\begin{align*} y = \sqrt {9+c_{1} {\mathrm e}^{x^{2}}} y = -\sqrt {9+c_{1} {\mathrm e}^{x^{2}}} \end{align*}

Solution by Mathematica

Time used: 1.856 (sec). Leaf size: 53

DSolve[y[x]*y'[x]==x*y[x]^2-9*x,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to -\sqrt {9+e^{x^2+2 c_1}} y(x)\to \sqrt {9+e^{x^2+2 c_1}} y(x)\to -3 y(x)\to 3 \end{align*}