Rearrange equation (solution of ODE)

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The discussion centers on the difficulty of rearranging a nonlinear first-order ordinary differential equation solution into a form that explicitly expresses R. The equation presented is ln(R) + (mR^(n-1))/(n-1) = w∞ξ + C. It is clarified that this equation does not have an analytic solution for R in terms of elementary functions. The thread concludes with the acknowledgment that the question has been answered, and no further discussion is necessary.
Juggler123
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I have determined the solution to a nonlinear first order ordinary differential equation but am struggling to rearrange the result, I have that

$$\\ln(R)+\frac{mR^{n-1}}{n-1}=\bar{w}_{\infty}\xi+C.$$

How would I rearrange this equation for $$R$$?
 
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Do you mean that R(x) is the function that solves a differential equation in the variable x ?
 
Juggler123 said:
I have determined the solution to a nonlinear first order ordinary differential equation but am struggling to rearrange the result, I have that

$$\\ln(R)+\frac{mR^{n-1}}{n-1}=\bar{w}_{\infty}\xi+C.$$

How would I rearrange this equation for $$R$$?

You can't. What you have is essentially <br /> \ln(R^{n-1}) + mR^{n-1} = A which doesn't have an analytic solution for R^{n-1} given A.
 
Sorry I should have been more clear. I have determined the solution R(\xi), the solution is

$$\ln(R(\xi))+\frac{mR(\xi)^{n-1}}{n-1}=\bar{w}_{\infty}\xi+C.$$

I simply need to rearrange this to say R(\xi)=\cdots
 
That was clear. And what you have been told that there is no solution in terms of elementary functions.
 
The question has been asked and answered, so I'm closing this thread.
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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