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 Author Comment/Response Fernando 11/17/09 11:40pm I have a function w with a coefficient A, I do some integrals with this function and then evaluate the derivative of the function respect to A equal to zero to solve for A. I want to assign this value to A, so this is what I am doing: w = A Sin[ Pi x/L] I = Integral[w^2,0,L] This integrates and gives me a function of A^2, then I do: sol=Solve[D[I,A]==0,A] Gives me a solution, with no problem, so I assign this value to A with A/.sol[[1]] Also no errors, but if I type w again, A has not been replaced. What am I missing? URL: ,

 Subject (listing for 'Replacing a variable with the root of an equati...') Author Date Posted Replacing a variable with the root of an equati... Fernando 11/17/09 11:40pm Re: Replacing a variable with the root of an eq... yehuda ben-s... 11/25/09 01:48am
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