deletions | additions       diff --git a/Summary.tex b/Summary.tex  index 575cadf..8ede3a7 100644  --- a/Summary.tex  +++ b/Summary.tex 
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\partial_x^2 & \partial_y\partial_x & \partial_z\partial_x \\  \partial_x\partial_y & \partial_y^2 & \partial_z\partial_y \\  \partial_x\partial_z & \partial_y\partial_z & \partial_z^2  \end{bmatrix} = \partial_i\partial_j  \\ \\ \nabla^2=  \begin{bmatrix}