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Exercise 11 - Operation Count

If A is a 823 X 823 matrix and one wishes to do a decomposition of the form A = LU with Doolittle's method. Compute separately the no of divisions, multiplications and additions required in the computation of L and U.

Answer:
n = 823
Addition = (2n3 - 3n2 + n) / 6 = 185475395
Multiplication =  (2n3 - 3n2 + n) / 6 = 185475395
Division = (n2 - n) / 2 = 338253
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