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Question
The matrix `[(1, 0, 0),(0, 2, 0),(0, 0, 4)]` is a ______.
Options
Identity matrix
Symmetric matrix
Skew-symmetric matrix
None of these
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Solution
The matrix `[(1, 0, 0),(0, 2, 0),(0, 0, 4)]` is a symmetric matrix.
Explanation:
Let A = `[(1, 0, 0),(0, 2, 0),(0, 0, 4)]`
A' = `[(1, 0, 0),(0, 2, 0),(0, 0, 4)]` = A
A' = A
So A is a symmetric matrix.
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