JEE Advanced · Mathematics · 18. Matrices
For 3 x 3 matrices M and N, which of the following statement(s) is (are) not correct?
- A NT MN is symmetric or skew-symmetric, according to as M is symmetric or skew-symmetric
- B MN - NM is skew symmetric for all symmetric matrices M and N
- C MN is symmetric for all symmetric matrices M and N
- D adj(M) adj(N) = adj (MN) for all invertible matrices M and N
Answer & Solution
Correct Answer
(D) adj(M) adj(N) = adj (MN) for all invertible matrices M and N
Step-by-step Solution
Detailed explanation
is symmetric if M is symmetric and skew-symmetric if M is skew-symmetric.
skew symmetric
hence not correct
Standard result is
skew symmetric
hence not correct
Standard result is
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