Finding the nth Derivative of a Rational Function

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Hello

I have this problem that I cannot get part of. I need function f^(n)(x) for 1/(5x-1). I have been working it out and I know the denominator is going to be (5x-1) ^ (n+1) but can not figure out the top.

So my question is how do I create a statement that evalutes the following

when x = 1 it equal -5
when x = 2 it equals -5 * -10 == 50
when x = 3 it equals -5 * -10 * -15 == -750

any hints would be great

Thanks

Peter
 
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Here's a hint

powp said:
Hello
I have this problem that I cannot get part of. I need function f^(n)(x) for 1/(5x-1). I have been working it out and I know the denominator is going to be (5x-1) ^ (n+1) but can not figure out the top.

Hint: as you differentiate, leave the coefficients factored. The answer your looking for involves a factorial and something else.
 
Thanks. This is driving me crazy. I have been thinking is has to do with factorials all this time but not sure in what way.
 
Please help

Can anybody please help me I am stuck. Please please please
 
Think I finally got it my answer -1^2(n!)5^n*(5x-1)^(-1-n)

Thanks for your help
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...

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