deletions | additions       diff --git a/Version2.tex b/Version2.tex  index 1c8f558..7a458d2 100644  --- a/Version2.tex  +++ b/Version2.tex 
...
Finally, substitute constants:  $$  T(n) = \frac{1}{2}(21n^2 \frac{1}{2}(7n^2  + n 15n  + 6) \in \mathcal{O}(n^2) $$