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If a = ⎡ ⎢ ⎣ 1 2 3 ⎤ ⎥ ⎦ Write Aat. - Mathematics

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Question

If  \[A = \begin{bmatrix}1 \\ 2 \\ 3\end{bmatrix}\] write AAT.

 

Sum

Solution

\[Given: A = \begin{bmatrix}1 \\ 2 \\ 3\end{bmatrix} \] 

\[ A^T = \begin{bmatrix}1 & 2 & 3\end{bmatrix}\] 

\[Now, \] 

\[A A^T = \begin{bmatrix}1 \\ 2 \\ 3\end{bmatrix}\begin{bmatrix}1 & 2 & 3\end{bmatrix}\] 

\[ \Rightarrow A A^T = \begin{bmatrix}1 & 2 & 3 \\ 2 & 4 & 6 \\ 3 & 6 & 9\end{bmatrix}\]

 

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Chapter 5: Algebra of Matrices - Exercise 5.6 [Page 62]

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RD Sharma Mathematics [English] Class 12
Chapter 5 Algebra of Matrices
Exercise 5.6 | Q 4 | Page 62

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