# Math Help - Im having trouble finding the second derivative of this equation

1. ## Im having trouble finding the second derivative of this equation

find the second derivative (0)

I get two different answer, one where i expand the brackets out, and one where i just make 1-q = p

2. $\left( \frac{1}{f} \right) ' = - \left( \frac{f'}{f^2} \right)$

Let $f = 1 - qe^{it}$

3. What reason would you have for setting 1- q= p?

4. Originally Posted by HallsofIvy
What reason would you have for setting 1- q= p?
its a stats module, probabiliity