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

question 39

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 $1 \times 4 , B$ is $4 \times 1$ .

• A) \(\mathrm { AB }\) is undefined, BA is \(4 \times 4\).
• B) \(\mathrm { AB }\) is \(4 \times 4\), BA is \(1 \times 1\).
• C) \(\mathrm { AB }\) is \(1 \times 1 , \mathrm { BA }\) is undefined.
• D) \(\mathrm { AB }\) is \(1 \times 1\), \(\mathrm { BA }\) is \(4 \times 4\).

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Definitions:

Economies of Scale

Cost advantages that enterprises obtain due to their scale of operation, with cost per unit of output generally decreasing with increasing scale.

Trade Gains

Benefits that countries obtain from engaging in international trade, such as increased variety of goods and specialization in production.

International Trade

International trade involves the exchange of goods and services across international borders or territories, enabling countries to expand markets and pursue economies of scale.

Variety

In economics, it represents the assortment or range of different products, services, or goods available in a market.