Exercise 2

In this section, we found the $LU$ factorization of the matrix $$A = \left[\begin{array}{rrr} 1 & 2 & 1 \\ -2 & -3 & -2 \\ 3 & 7 & 4 \\ \end{array}\right]$$ in one of the activities, without using partial pivoting. Apply a sequence of row operations, now using partial pivoting, to find an upper triangular matrix $U$ that is row equivalent to $A$.