Finding Solutions for ODE y'=2*sqrt(|y|) with Initial Condition y(0)=0

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Homework Statement


Given this ODE :
y'=2*sqrt(|y|) , y(0)=0 ...
Can we find two different soloutions around (0,0) ? If there are, find them... If there are no two different soloutions around (0,0) - explain why...

Help is needed! TNX


Homework Equations


The Attempt at a Solution

 
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y'= dy/dx= 2\sqrt{y}= 2y^{1/2}
so
y^{-1/2}dy= 2dx
Integrate to get one solution. Another obvious solution is y(x)= 0.
 
Hey there hallsofIvy...I did it this way too, but I really thought that we must have a contradiction or something from the existence and uniqueess theorem...NVM...

TNX a lot for your help!
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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