Question 3
Let A = [1 2 0; 1 1 h; 0 h 1], where h is a real constant.
(a) Find the inverse of A by using
(i) the inversion algorithm.
(ii) the adjoint method.
(b) Use the matrix inverse method and the result of (a) to solve each of the following linear systems.
(i) 2x1 + 4x2 = -2,
2x2 - x3 = 1,
x1 + x2 - 2x3 = R+1.
(ii) x1 + x2 = R+1,
2x1 + x2 + 3x3 = 2,
3x2 + x3 = R+3.
(c) Use Cramer's rule to solve the system of linear equations in (b)(ii).
(d) Let B be a 3x3 matrix such that det(B) = R+2. Find the following in terms of h.
(i) det(3A^2B^T)
(ii) det(adj(AB))