title: Tree method with 8T(n/2) +n^2
body: <p>I'm trying to solve this problem, but I think I haven't understood how to do it correctly. The first thing I do in this type of exercises is taking the bigger value in the row (in this case is n^2) and divide it multiple times, so I can find what kind of relation there is between the values. After found the relation, I try to mathematically found its value and then as the final step, I multiply the result for the root. In this case the result should be n^3. How is possible?
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