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 Author Comment/Response Vassilis 11/24/07 04:56am Hi All, I'd like some help with respect to a problem I have with the FindRoot, NSolve and FindInstance functions. I define the function f as follows: f[x_]:={ y/.FindRoot[y^3+1==x,{y,x}][[1]] }[[1]] f[x] returns the root of the equation y^3 + 1 == x, i.e. the value (x-1)^(1/3). f[x] has obviously a unique root at x=1. If I now try to find f[x]'s root with FindRoot, for example like FindRoot[f[x]==0,{x,3}] Mathematica (v 5.2) returns error messages and no solution. The same happens if I use instead NSolve or FindInstance. Can you guys explain why this happens and suggest a remedy? Needless to say, the actual problem I try to tackle involves much more complicated functions... Thanks, Vassilis URL: ,

 Subject (listing for 'A problem with FindRoot') Author Date Posted A problem with FindRoot Vassilis 11/24/07 04:56am Re: A problem with FindRoot yehuda ben-s... 12/02/07 11:32am
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