1. (6 marks) CO-1: Answer any one from Questions-(1a-1b). Marks break down are as stated. (a) (6 marks) A linear system is described by the matrix equation Ax=b where A is a square nn matrix, x and b are n1 column matrices. If the matrix A is decomposed into a product of unit lower triangular matrix L and an upper triangular matrix U, show that detA=detU. (b) i. (2 marks) Define an over-determined system. ii. (2 marks) Name the methods that you learned to solve an over-determined system. iii. (2 marks) Let the over-determined system is described by Ax=b where the matrix A is a 42 matrix. Since detA does not exist, state the condition to find a solution of the over-determined system