deletions | additions       diff --git a/We_can_define_the_Fourier__.tex b/We_can_define_the_Fourier__.tex  index 5125c77..cedda27 100644  --- a/We_can_define_the_Fourier__.tex  +++ b/We_can_define_the_Fourier__.tex 
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\begin{equation}  M = at^3 + bt^2 + ct + d,  \end{equation}  where $a=(\pi/3)\ddot{f}_k$, $a=(\pi/3)\ddot{f_k}$,  $b = \pi \dot{f}_k$, \dot{f_k}$,  $c = 2\pi(f_k-f)$ and $d=0$ and make the substitution $t = Az+B$. To get the derivative ${\rm d}z$ we have \begin{equation}  \frac{{\rm d}t}{{\rm d} z} = A,  \end{equation}