What is 2M?
M=[3 5]
[-4 0]
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Answer:
2M will be:
[tex]2\begin{pmatrix}3&5\\ -4&0\end{pmatrix}=\begin{pmatrix}6&10\\ -8&0\end{pmatrix}[/tex]
Therefore, the 2nd option is true.
Step-by-step explanation:
Given the matrix
[tex]M=\begin{pmatrix}3&5\\ -4&0\end{pmatrix}[/tex]
Multiplying by 2 will basically be a scalar multiplication.
Therefore, multiply each of the matrix elements by a scalar.
[tex]2M=2\begin{pmatrix}3&5\\ \:-4&0\end{pmatrix}[/tex]
[tex]=\begin{pmatrix}2\cdot \:3&2\cdot \:5\\ 2\left(-4\right)&2\cdot \:0\end{pmatrix}[/tex]
[tex]=\begin{pmatrix}6&10\\ -8&0\end{pmatrix}[/tex]
Hence, 2M will be:
[tex]2\begin{pmatrix}3&5\\ -4&0\end{pmatrix}=\begin{pmatrix}6&10\\ -8&0\end{pmatrix}[/tex]
Therefore, the 2nd option is true.