Rearrange equation (solution of ODE)

AI Thread Summary
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.
 
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