End of differential equation, quick alegbra Q

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Homework Statement


I just solved a differential equation and got the problem down to its implicit solution:
y/√(1+y2) = x3+C where C is an arbitrary constant
My question now is, how can I solve for y? I can't get past the algebra. Thanks!


Homework Equations





The Attempt at a Solution

 
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Square both sides. Solve for y^2. Take a square root. Come on. Try it.
 
Square both sides and bring the bottom part to the other side. You'll get

y^2 = (1+y^2)(x^3 + c)^2

Then multiply out and regroup.

y^2 -y^2(x^3 + c)^2 = (x^3 + c)^2

then you'll get y^2 = \frac{(x^3+c)^2}{1-(x^3+c)^2}

So y = \sqrt{\frac{(x^3+c)^2}{1-(x^3+c)^2}}
 
thank you!
 
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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