The Sizes of Two Matrices a and B Are Given $A$

question 3

Multiple Choice

The sizes of two matrices A and B are given. Find the sizes of the product AB and the product BA, if the products are
defined.
- $A$ is $2 \times 1$ , B is $1 \times 1$ .

• A) \(\mathrm { AB }\) is \(2 \times 1 , \mathrm { BA }\) is undefined.
• B) \(\mathrm { AB }\) is \(1 \times 2 , \mathrm { BA }\) is \(1 \times 1\).
• C) \(\mathrm { AB }\) is \(2 \times 2 , \mathrm { BA }\) is \(1 \times 1\).
• D) \(A B\) is undefined, \(B A\) is \(1 \times 2\).

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Definitions:

Inspection

The visual examination of the patient’s entire body and overall appearance.

Proctologic

Pertaining to proctology, a branch of medicine focused on the diagnosis and treatment of disorders of the rectum and anus.

Anal Examinations

Medical procedures that involve the inspection and evaluation of the anus and rectum for disease or abnormalities.

Rectal Examinations

A physical examination in which a doctor or nurse inserts a finger into the rectum to check for abnormalities of organs or other structures in the pelvis or abdomen.