Question

Which of the following statements is/are correct?
I. Adjoint of a unit matrix is a unit matrix.
II. $A(\text{adj}A)=(\text{adi}A)A=|A|I$
III. Adjoint of a symmetric matrix is symmetric.
IV. Adjoint of a diagonal matrix is a diagonal matrix.

• A. I
• B. II
• C. I or II
• D. All statements are correct

Answer 1

Answer: (D)

All statements are correct.