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If the matrix A is both symmetric and skew symmetric, then ______.

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Question

If the matrix A is both symmetric and skew symmetric, then ______.

Options

  • A is a diagonal matrix

  • A is a zero matrix

  • A is a square matrix

  • None of these

MCQ
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Solution

If the matrix A is both symmetric and skew symmetric, then A is a zero matrix.

Explanation:

Consider the matrix A.

Clearly A' = A and A' = –A 

∴ A = –A 

⇒ 2A = 0 

⇒ A = 0 

∴ A is a zero matrix.

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Chapter 3: Matrices - Miscellaneous Exercise on Chapter 3 [Page 73]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 3 Matrices
Miscellaneous Exercise on Chapter 3 | Q 10. | Page 73

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