The Sizes of Two Matrices Are Given $A$ Is $2 \times 1$

question 453

Multiple Choice

The sizes of two matrices are given. Find the size of the product AB and the size of the product BA, if the given product
can be calculated.
- $A$ is $2 \times 1$ ; B is $1 \times 1$ .

• A) \(\mathrm { AB }\) cannot be calculated; \(\mathrm { BA }\) is \(1 \times 2\).
• B) \(\mathrm { AB }\) is \(1 \times 2\); \(\mathrm { BA }\) is \(1 \times 1\).
• C) \(\mathrm { AB }\) is \(2 \times 1\); BA cannot be calculated.
• D) \(\mathrm { AB }\) is \(2 \times 2\); \(\mathrm { BA }\) is \(1 \times 1\).

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Definitions:

Null Hypothesis

The hypothesis that there is no significant difference or effect, and any observed difference is due to sampling or experimental error.

Normally Distributed

Refers to a probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean.

Confidence Interval

A range of values derived from sample statistics that is likely to contain the value of an unknown population parameter.

Population Means

The average value of a particular characteristic within a total population.