Question:
Compute \(\begin{bmatrix}1&0 \\ 0&1\end{bmatrix}\begin{bmatrix}2&-3 \\ 0&4\end{bmatrix}=\) ?
Compute \(\begin{bmatrix}1&0 \\ 0&1\end{bmatrix}\begin{bmatrix}2&-3 \\ 0&4\end{bmatrix}=\) ?
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\(I\) is the multiplicative identity of matrices: \(IA=AI=A\).
Updated On: Oct 17, 2025
- \(\begin{bmatrix}2&-3
0&4\end{bmatrix}\) - \(\begin{bmatrix}2&0
0&4\end{bmatrix}\) - \(\begin{bmatrix}3&-3
0&5\end{bmatrix}\) - \(\begin{bmatrix}1&0
0&1\end{bmatrix}\)
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The Correct Option is A
Solution and Explanation
Idea. Multiplying by the identity \(I\) leaves a matrix unchanged, just like multiplying a number by \(1\).
So \(I\cdot A=A\) and the product equals the second matrix itself.
So \(I\cdot A=A\) and the product equals the second matrix itself.
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