Ways to compute AB=C (by Fundamental Law of Matrix Multiplication and dot product).The entry in row i and column j of AB is (row i of A)*(row j of B).             If A and B are n by n, so is AB. It contains n^2 dot products, rows of A times column of B. Each               dot product needs n multiplications, so the computation of AB uses n^3 multiplications. Matrix A times every column of B (the column picture of AB) A[b1...bn]= [Ab1..Abn]Every row of A times matrix B [row i of A]B = [row i of AB].Columns multiply rows. AB = (col 1)(col 2) + (col 2)(row 2) + (col 3)(row 3)