Hello, pepelepew23!

What is the product of the following two matrices?

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The other choices are irrelevant to my question. . Really?

In my book, the answer is A, while I believe it is B

. . because if c_{1 }= r_{2 }, then a product exists.

However, this is not upheld in this given question because c_{1 }= 1, and r_{2}= 4.

Not true . . . The first matrix hasfourcolumns: c_{1}= 4.

We are multiplying a matrix by a matrix.

The product is a matrix . . . That'sone rowandtwo columns: .

The book's answer is wrong; it is a matrix . . . the wrong shape!

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