alleryIf $A$ is of order $2\times3$ and $B$ is of order $3\times4$, then $AB$ has order:
A$3\times3$
Bnot defined
C$2\times4$
D$4\times2$
Answer & Solution
Correct answer: C. $2\times4$
Inner dimensions match (3=3); the product takes the outer dimensions: 2×4.
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