Hi all,

I am examining the approximate solutions to the Schrodinger equation using the WKB method. I have a simple differentiation query as follows. I want to find A.

$\displaystyle 2A'(x) \phi (x)+A(x) \phi^{''} (x) = 0$ or

$\displaystyle (A^2(x) \phi^{'} (x))' = 0$ can be solved by

$\displaystyle A^2(x) \phi^{'} (x) = C^2$

or $\displaystyle A=\frac{C}{\sqrt{\phi^{'}}}$

How do you get to the 3rd or 4th line?

Thanks