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The matrix A = ⎡ ⎢ ⎣ 1 0 0 0 2 0 0 0 4 ⎤ ⎥ ⎦ is - Mathematics

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Question

The matrix   \[A = \begin{bmatrix}1 & 0 & 0 \\ 0 & 2 & 0 \\ 0 & 0 & 4\end{bmatrix}\] is

 

Options

  • identity matrix

  • symmetric matrix

  • skew-symmetric matrix

  • diagonal matrix

MCQ
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Solution

Given: 

\[A = \begin{bmatrix}1 & 0 & 0 \\ 0 & 2 & 0 \\ 0 & 0 & 4\end{bmatrix}\]


\[A^T = \begin{bmatrix}1 & 0 & 0 \\ 0 & 2 & 0 \\ 0 & 0 & 4\end{bmatrix}^T \] 

\[ = \begin{bmatrix}1 & 0 & 0 \\ 0 & 2 & 0 \\ 0 & 0 & 4\end{bmatrix}\] 

\[ = A\]

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Chapter 5: Algebra of Matrices - Exercise 5.7 [Page 69]

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RD Sharma Mathematics [English] Class 12
Chapter 5 Algebra of Matrices
Exercise 5.7 | Q 45 | Page 69

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