Given A E Rnxn, B E Rnxm, C E Rmxn, D E Rmxm, a E R", and b E Rm. Assume D and (A - BD-'C) are invertible. Let X = A B C D 1. Give the expression of the solution to [a BJ =. Also, give the expression of X-! 2. Prove that det(X) = det(D)det(A - BD-10)