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Show that the matrix A = [(1, –1, 5),(–1, 2, 1),(5, 1, 3)] is a symmetric matrix.

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Question

Show that the matrix A = `[(1, -1, 5),(-1, 2, 1),(5, 1, 3)]` is a symmetric matrix.

Sum
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Solution

Given, A = `[(1, -1, 5),(-1, 2, 1),(5, 1, 3)]`

So, A' = `[(1, -1, 5),(-1, 2, 1),(5, 1, 3)]` 

∵ A' = A Hence, it is proved that the matrices are

A = `[(1, -1, 5),(-1, 2, 1),(5, 1, 3)]` is a symmetric matrix.

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Chapter 3: Matrices - EXERCISE 3.3 [Page 67]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 3 Matrices
EXERCISE 3.3 | Q 7. (i) | Page 67

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