Finding the nth Derivative of a Fraction

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EngWiPy
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Hello,

Is there a general form for the nth derivative for a fraction?

Thanks in advance.
 
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Hello saeddawoud! :smile:

General form for a product:

(fg)(n) = f(n)g + nC1f(n-1)g(1) + … + fg(n) …

so the form for f(1/g) is … ? :wink:
 
tiny-tim said:
Hello saeddawoud! :smile:

General form for a product:

(fg)(n) = f(n)g + nC1f(n-1)g(1) + … + fg(n) …

so the form for f(1/g) is … ? :wink:

Thank you, it is really helpful, but how to determine the coefficients of each term in general form?

Regards
 
saeddawoud said:
Thank you, it is really helpful, but how to determine the coefficients of each term in general form?

Regards

The coefficients are just the binomial coefficients. That's what the nC1 in Tiny Tim's expression is. Written in summation notation:

[tex](fg)^{(n)} = \sum_{k=0}^{n}\frac{n!}{k!(n-k)!}f^{(n-k)}g^{(k)}[/tex]