1.57 problem 57

Internal problem ID [7638]

Book: Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section: Chapter 1, linear first order
Problem number: 57.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [_quadrature]

Solve \begin {gather*} \boxed {y^{\prime }-\sqrt {{| y|}}=0} \end {gather*}

Solution by Maple

Time used: 0.016 (sec). Leaf size: 31

dsolve(diff(y(x),x) - sqrt(abs(y(x)))=0,y(x), singsol=all)
 

\[ x -\left (\left \{\begin {array}{cc} -2 \sqrt {-y \relax (x )} & y \relax (x )\le 0 \\ 2 \sqrt {y \relax (x )} & 0<y \relax (x ) \end {array}\right .\right )+c_{1} = 0 \]

Solution by Mathematica

Time used: 0.257 (sec). Leaf size: 31

DSolve[y'[x] - Sqrt[Abs[y[x]]]==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to \text {InverseFunction}\left [\int _1^{\text {$\#$1}}\frac {1}{\sqrt {| K[1]| }}dK[1]\&\right ][x+c_1] \\ y(x)\to 0 \\ \end{align*}