Matrices
- Thread starter Pdg1976
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Dr.Peterson
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What do you think it might be? What are you unsure of about that?
Can you state your understanding of what the question means, so we can know where to start in helping? That is, how would you calculate 8A - B?
Can you state your understanding of what the question means, so we can know where to start in helping? That is, how would you calculate 8A - B?
HallsofIvy
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You multiply a number by a matrix by multiplying each number in the matrix:
\(\displaystyle N\begin{bmatrix}a & b \\ c & d \end{bmatrix}= \begin{bmatrix} aN & bN \\ cN & dN\end{bmatrix}\).
You subtract (or add) matrices by subtracting (or adding) "corresponding" numbers in the two matrices:
\(\displaystyle \begin{bmatrix}a & b \\ c & d \end{bmatrix}- \begin{bmatrix}u & v \\ w & x\end{bmatrix}= \begin{bmatrix}a- u & b- v \\ c- w & d- x \end{bmatrix}\(\displaystyle .\)\)
\(\displaystyle N\begin{bmatrix}a & b \\ c & d \end{bmatrix}= \begin{bmatrix} aN & bN \\ cN & dN\end{bmatrix}\).
You subtract (or add) matrices by subtracting (or adding) "corresponding" numbers in the two matrices:
\(\displaystyle \begin{bmatrix}a & b \\ c & d \end{bmatrix}- \begin{bmatrix}u & v \\ w & x\end{bmatrix}= \begin{bmatrix}a- u & b- v \\ c- w & d- x \end{bmatrix}\(\displaystyle .\)\)