Use the Fundamental Identities to Find the Value of the Trigonometric

question 196

True/False

Use the fundamental identities to find the value of the trigonometric function.
- $$\cos \frac { \pi } { 72 } = \cos \frac { \pi } { 9 } \cos \frac { \pi } { 8 } - \sin \frac { \pi } { 9 } \sin \frac { \pi } { 8 }$$

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Definitions:

Social Communication

The exchange of information and expressions between individuals through verbal and non-verbal means.

Classical Conditioning

A learning process that occurs when two stimuli are repeatedly paired; a response that is at first elicited by the second stimulus is eventually elicited by the first stimulus alone.

Operant Conditioning

A learning process by which the consequences of an action affect the likelihood of its occurrence in the future, central to behavioral psychology.

Imitation

The action of using someone or something as a model and attempting to replicate their behavior, actions, or attributes.