Nonlinear ODE: Analytical Solution?

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Nonlinear 1st order ODE

\frac{dH}{dt}=B-A*(H-Z)^{3/2}
where:
B,A and Z are known values

H=f(t); H is function of t




I've already solve this ODE numerically using a 4th order RK routine. But my question is, it is possible to get an analytical solution for H(t)?
 
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first let h = H-Z, then you get

h' = b-ah^(3/2)
 
mathematica finds it messy...
http://www.wolframalpha.com/input/?i=h'(t)+%3D+b-a*(h(t))^(3/2)
 
lanedance said:
first let h = H-Z, then you get

h' = b-ah^(3/2)

lanedance said:
mathematica finds it messy...
http://www.wolframalpha.com/input/?i=h'(t)+%3D+b-a*(h(t))^(3/2)

I have try it plugging it with h=H-Z in mathematica but the solution is a mess. I really don't know how to get an expression for H(t) from this. :-/
 
there may not be one...
 
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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