Factor a matrix as A=LU When necessary, factor a matrix as PA=LU Problem 1: Let ? = [ 1 2 3 0 2 7 3 6 4 ]. Notice that [ 1 0 0 0 1 0 3 0 1 ] [ 1 2 3 0 2 7 3 6 4 ] = [ 1 2 3 0 2 7 0 0 5 ]. Write ? as the product of a lower-triangular and upper-triangular matrix. Problem 2: Let ? = [ 2 1 4 0]. Write ? as the product of a lower-triangular and upper-triangular matrix