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:

Certification

The process of verifying the attributes, characteristics, or quality of someone or something, often resulting in a formal document.

Refuses to Bargain

Occurs when an employer or union does not engage in good faith negotiation over wages, hours, and other terms of employment.

Hiring Hall

A place operated by a labor union or an employer association where workers are matched with available jobs, typically in the maritime and construction industries.

Duty of Fair Representation

The obligation of a union to represent all members fairly, impartially, and in good faith, particularly during collective bargaining and grievance processes.