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This question tests if a students understands when matrices are conformable

", "licence": "Creative Commons Attribution-NonCommercial 4.0 International"}, "statement": "

Conformable Matrices for Multiplication

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For each of the following pairs of matrices, determine whether they are conformable for multiplication

", "advice": "

We are asked to determine whether two matrices are conformable for multiplication

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To do this, we must determine the dimensions of each matrix

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a)

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$\\boldsymbol{A}$ has $\\var{n1q1}$ columns and $\\boldsymbol{B}$ has $\\var{m2q1}$ rows

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Since both of these values are $\\var{n1q1}$, the product $\\boldsymbol{AB}$ is defined and the matrices are conformable

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\n
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Since $\\var{n1q1}$ is not equal to $\\var{m2q1}$, the product $\\boldsymbol{AB}$ is not defined and the matrices are not conformable

\n
\n

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b)

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$\\boldsymbol{C}$ has $\\var{n1q2}$ columns and $\\boldsymbol{D}$ has $\\var{m2q2}$ rows

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Since both of these values are $\\var{n1q2}$, the product $\\boldsymbol{CD}$ is defined and the matrices are conformable

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Since $\\var{n1q2}$ is not equal to $\\var{m2q2}$, the product $\\boldsymbol{CD}$ is not defined and the matrices are not conformable

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\n

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c)

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$\\boldsymbol{E}$ has $\\var{n1q3}$ columns and $\\boldsymbol{F}$ has $\\var{m2q3}$ rows

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Since both of these values are $\\var{n1q3}$, the product $\\boldsymbol{EF}$ is defined and the matrices are conformable

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\n
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Since $\\var{n1q3}$ is not equal to $\\var{m2q3}$, the product $\\boldsymbol{AB}$ is not defined and the matrices are not conformable

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\n

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\n

\n
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Consider:

\n

$$
\\boldsymbol{A} = \\var{A}, \\boldsymbol{B} = \\var{B}
$$

\n

The product $\\boldsymbol{AB}$ [[0]], and therefore the matrices are [[1]].

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Consider:

\n

$$
\\boldsymbol{C} = \\var{C}, \\boldsymbol{D} = \\var{D}
$$

\n

The product $\\boldsymbol{CD}$ [[0]], and therefore the matrices are [[1]].

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Consider:

\n

$$
\\boldsymbol{E} = \\var{E}, \\boldsymbol{F} = \\var{F}
$$

\n

The product $\\boldsymbol{EF}$ [[0]], and therefore the matrices are [[1]].

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