44.4.35 problem 16

Internal problem ID [7048]
Book : A First Course in Differential Equations with Modeling Applications by Dennis G. Zill. 12 ed. Metric version. 2024. Cengage learning.
Section : Chapter 2. First order differential equations. Section 2.1 Solution curves without a solution. Exercises 2.1 at page 44
Problem number : 16
Date solved : Wednesday, March 05, 2025 at 04:04:00 AM
CAS classification : [_Riccati]

\begin{align*} y^{\prime }&=x \left (y-4\right )^{2}-2 \end{align*}

Maple. Time used: 0.023 (sec). Leaf size: 113
ode:=diff(y(x),x) = x*(y(x)-4)^2-2; 
dsolve(ode,y(x), singsol=all);
 
\[ y = \frac {2 \left (2^{{1}/{3}} \operatorname {AiryAi}\left (1, -\frac {8 \,2^{{2}/{3}} x}{\left (-32 i\right )^{{2}/{3}}}\right ) \left (1+i \sqrt {3}\right ) c_{1} +2^{{1}/{3}} \operatorname {AiryBi}\left (1, -\frac {8 \,2^{{2}/{3}} x}{\left (-32 i\right )^{{2}/{3}}}\right ) \left (1+i \sqrt {3}\right )+\operatorname {AiryAi}\left (-\frac {8 \,2^{{2}/{3}} x}{\left (-32 i\right )^{{2}/{3}}}\right ) c_{1} +\operatorname {AiryBi}\left (-\frac {8 \,2^{{2}/{3}} x}{\left (-32 i\right )^{{2}/{3}}}\right )\right ) 2^{{2}/{3}}}{\left (1+i \sqrt {3}\right ) \left (c_{1} \operatorname {AiryAi}\left (1, -\frac {8 \,2^{{2}/{3}} x}{\left (-32 i\right )^{{2}/{3}}}\right )+\operatorname {AiryBi}\left (1, -\frac {8 \,2^{{2}/{3}} x}{\left (-32 i\right )^{{2}/{3}}}\right )\right )} \]
Mathematica. Time used: 0.192 (sec). Leaf size: 113
ode=D[y[x],x]==x*(y[x]-4)^2-2; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 
\begin{align*} y(x)\to -\frac {2^{2/3} \operatorname {AiryBi}\left (\sqrt [3]{2} x\right )-4 \operatorname {AiryBiPrime}\left (\sqrt [3]{2} x\right )+2^{2/3} c_1 \operatorname {AiryAi}\left (\sqrt [3]{2} x\right )-4 c_1 \operatorname {AiryAiPrime}\left (\sqrt [3]{2} x\right )}{\operatorname {AiryBiPrime}\left (\sqrt [3]{2} x\right )+c_1 \operatorname {AiryAiPrime}\left (\sqrt [3]{2} x\right )} \\ y(x)\to 4-\frac {2^{2/3} \operatorname {AiryAi}\left (\sqrt [3]{2} x\right )}{\operatorname {AiryAiPrime}\left (\sqrt [3]{2} x\right )} \\ \end{align*}
Sympy
from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq(-x*(y(x) - 4)**2 + Derivative(y(x), x) + 2,0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 
ValueError : Rational Solution doesnt exist