# simple differentiation

• May 4th 2011, 02:39 AM
canger
simple differentiation

Differentiate 1/(1-x)
(w.r.t.x)

It's for part of a ridiculously hard stats problem, I just can't recall this simple rule!

Thanks
• May 4th 2011, 02:42 AM
Prove It
Rewrite it as (1 - x)^{-1} and then use the chain rule...
• May 4th 2011, 02:46 AM
bugatti79
Quote:

Originally Posted by canger

Differentiate 1/(1-x)
(w.r.t.x)

It's for part of a ridiculously hard stats problem, I just can't recall this simple rule!

Thanks

Use Quotient rule

$\displaystyle \frac{ vu' - uv'}{v^2}$ where u = 1 and v =(1-x) you should get

1/(1-x)^2
• May 4th 2011, 03:56 AM
canger
thank you both
Ta!