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Explicit derivatives

Hey there i have defined this function: G[x_] := Log[x] and the nth derivative fnm[x, n] := Derivative[n][g][x]. When i try to print fnm[x, n], i just get the general answer g^(n)[x]. I am undable to get the answer as an explicit function in x. The furmulas are correct as i am able to get correct numeric results from them. What shall i do ?

Regards Andreas Ø (new user)
POSTED BY: Andreas Madsen
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but unfortunately it will not give the explicit answer for the general case of n - it returns Log^(n)(x) in stead of the actual expression in just n and x..

Ok, found a way. Use Lichtblau's method as shown here.

  nthDeriv[f_, x_, n_] := n!*SeriesCoefficient[f[x], {x, x, n}]

And now type

   nthDeriv[Log, x, n]

gives

enter image description here
POSTED BY: Nasser M. Abbasi

That worked! Thank you very much :)
POSTED BY: Andreas Madsen

Thanks for the answer, but unfortunately it will not give the explicit answer for the general case of n - it returns Log^(n)(x) in stead of the actual expression in just n and x..

In case of n=2, it works fine, but that was not my problem..
POSTED BY: Andreas Madsen
POSTED BY: Nasser M. Abbasi
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