Question

find the element of \\(a_{21}\\) of the given matrix.
\\a = \

$$\begin{bmatrix} 1 & -1 & 3 \\\\ 2 & 0 & 6 \\end{bmatrix}$$

\\

-1

2

Explanation:

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<reasoning>

Identify the target element index

Using the Matrix Element Indexing knowledge point
\[
a_{ij} \implies i = 2, \quad j = 1
\]

Locate the element in the matrix

Using the Matrix Element Indexing knowledge point
\[
A =

$$\begin{bmatrix} 1 & -1 & 3 \\ 2 & 0 & 6 \end{bmatrix}$$

\implies a_{21} = 2
\]
</reasoning>

<answer>
<mcq-option>-1</mcq-option>
<mcq-correct>2</mcq-correct>
</answer>

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Answer:

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<reasoning>

Identify the target element index

Using the Matrix Element Indexing knowledge point
\[
a_{ij} \implies i = 2, \quad j = 1
\]

Locate the element in the matrix

Using the Matrix Element Indexing knowledge point
\[
A =

$$\begin{bmatrix} 1 & -1 & 3 \\ 2 & 0 & 6 \end{bmatrix}$$

\implies a_{21} = 2
\]
</reasoning>

<answer>
<mcq-option>-1</mcq-option>
<mcq-correct>2</mcq-correct>
</answer>

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