4.2.49 \(y'(x)=\sqrt {| y(x)| }\)

ODE
\[ y'(x)=\sqrt {| y(x)| } \] ODE Classification

[_quadrature]

Book solution method
Separable ODE, Independent variable missing

Mathematica
cpu = 0.240552 (sec), leaf count = 26

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

Maple
cpu = 0.098 (sec), leaf count = 31

\[\left [x -\left (\left \{\begin {array}{cc}-2 \sqrt {-y \left (x \right )} & y \left (x \right )\le 0 \\ 2 \sqrt {y \left (x \right )} & 0<y \left (x \right ) \end {array}\right .\right )+\textit {\_C1} = 0\right ]\] Mathematica raw input

DSolve[y'[x] == Sqrt[Abs[y[x]]],y[x],x]

Mathematica raw output

{{y[x] -> InverseFunction[Inactive[Integrate][1/Sqrt[Abs[K[1]]], {K[1], 1, #1}] 
& ][x + C[1]]}}

Maple raw input

dsolve(diff(y(x),x) = abs(y(x))^(1/2), y(x))

Maple raw output

[x-piecewise(y(x) <= 0,-2*(-y(x))^(1/2),0 < y(x),2*y(x)^(1/2))+_C1 = 0]