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Re: calculation (Perhaps Solve could do more with rational exponents???)

Solve[r^(5/2)/((r^(1/2)-1)^(1/3))==a,r] results in roots of a 15th order
polynomial (taking only a fraction of a second), while
Solve[r^(5/2)/((r^(1/3)-1)^(1/3))==a,r] had to be abended for spending
far more time and memory than seemed reasonable (Pentium II 266MHz w/
128 MBytes).  Making an "obvious" transformation
results in roots of a 45th order polynomial (taking only a fraction of a

To (my)(IMHO etc) human eyes both equations seem of "equal"
complexity... could Solve be extended to be more aggressive with
expressions involving rational powers???

Saeed Esmaily Rashid <> wrote in article
> Hello!
> My name is Saeed and i'm studying physics. I have a problem which ihope
> someone can help me with it. I have an equation
> .001422409738*R^(73/80)*(R^(1/2)-1)^(-13/40) == .04
> i'm using the Solve function in Mathematica 3.0 to solve it for R, but
> it calculats endlessly and takes very long time. the question is that
> is there any way to optimize this equation or using another function in
> Mathematica 3.0 to make it faster to calculate?
> Regards 

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