# What's this equation come from?

1. May 5, 2013

### pattisahusiwa

I have an equation like this,

$\frac{dZ}{zD\beta} = \frac{d}{d\beta}\ln Z$,

is it from $\frac{d}{d\beta}\frac{dZ}{Z}$ or from...?

How we can prove this relation?

2. May 5, 2013

### Office_Shredder

Staff Emeritus
Is your equation supposed to be
$$\frac{1}{Z} \frac{ dZ}{d\beta} = \frac{d}{d\beta} \ln(Z)$$
If so, this is just the chain rule

3. May 5, 2013

### pattisahusiwa

Thank you for quick replay.

Yes, your relation is correct too. If this is a chain rule, so can i write them like one in the first thread?

4. May 6, 2013

### pattisahusiwa

Hi all, I just want to know that my relation is correct or not?

$$\frac{1}{Z}\frac{dZ}{d\beta} = \frac{d}{d\beta}\int\frac{dZ}{Z} = \frac{d}{d\beta}\left(\ln Z\right)$$