Let A and B be two non-singular, square matrices of same order, and

A. (AB)^–1 = B^–1.A^–1

B. (A + B)^–1 = B^–1 + A^–1

C. adj. A = |A|.A^–1

D. det(A^–1) = [det A]^–1

Choose the correct answer from the options given below

A, C and D only

A. (AB)^–1 = B^–1.A^–1

B. (A + B)^–1 ≠ B^–1 + A^–1

C. adj. A = |A|¹

$adj(A) = |A|\frac{1}{A}⇒|A|.A^{-1}$

D. det(A^–1) = [det A]^–1

∴ A, C, & D options are correct.

So option 4th is correct.