77.1.67 problem 87 (page 123)

Internal problem ID [17878]
Book : V.V. Stepanov, A course of differential equations (in Russian), GIFML. Moscow (1958)
Section : All content
Problem number : 87 (page 123)
Date solved : Thursday, March 13, 2025 at 11:08:14 AM
CAS classification : [_quadrature]

\begin{align*} y^{\prime }&=\sqrt {y} \end{align*}

Maple. Time used: 0.001 (sec). Leaf size: 14
ode:=diff(y(x),x) = y(x)^(1/2); 
dsolve(ode,y(x), singsol=all);
 
\[ \sqrt {y}-\frac {x}{2}-c_{1} = 0 \]
Mathematica. Time used: 0.098 (sec). Leaf size: 20
ode=D[y[x],x]==Sqrt[y[x]]; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 
\begin{align*} y(x)\to \frac {1}{4} (x+c_1){}^2 \\ y(x)\to 0 \\ \end{align*}
Sympy. Time used: 0.178 (sec). Leaf size: 17
from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq(-sqrt(y(x)) + Derivative(y(x), x),0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 
\[ y{\left (x \right )} = \frac {C_{1}^{2}}{4} + \frac {C_{1} x}{2} + \frac {x^{2}}{4} \]