2. Recall the notion of (2, j)-cofactor Caj of a square matrix from our discussion of determinants. Given an n x n matrix A, define an n x n matrix A by C11 C21 ... Cnl C12 C22 ... Cn2 A' = [Cj] = Cin Can ... Cnn (a) Prove that for i = 1, ...,n, the dot product of the i-th row of A and the i-th column of A' is det( A)