Maths-
General
Easy
Question
The inverse of a skew symmetric matrix (if it exists) is -
- a symmetric matrix
- a skew symmetric matrix
- diagonal matrix
- None of these
The correct answer is: a skew symmetric matrix
We have A' = – A
Now, AA–1 = A–1 A = In
(AA–1)' = (A–1 A)' = (In)'
(A–1)' A' = A'(A–1)'= In
(A–1)' (–A) = (–A) (A–1)' = In
Thus, (A–1)' = –(A–1)
[inverse of a matrix is unique].
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