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:

Calcium Crystals

Mineral deposits found in various tissues of the body, often in bones and teeth, contributing to their hardness.

Silica Crystals

Rigid, crystalline structures made of silicon dioxide (SiO2), found in nature as quartz and used industrially and scientifically for various applications.

Spicules

Small, spike-shaped structures found in certain animals like sponges, serving as a skeletal element.

Radial Symmetry

Body plan in which similar parts are arranged around a central axis, like spokes of a wheel.