Show That the Equation Is Not an Identity by Finding $$\frac { \sin 3 x + \sin 9 x } { \cos 9 x - \cos 3 x } = ?$$

question 39

Multiple Choice

Show that the equation is not an identity by finding a value of x for which both sides are defined but not equal.
- $$\frac { \sin 3 x + \sin 9 x } { \cos 9 x - \cos 3 x } = ?$$

• A) \(- \cot 3 x\)
• B) \(\tan 3 x + \tan 9 x\)
• C) \(\cot 3 x\)
• D) \(\tan 6 x\)

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Definitions:

Efficient Market

A market in which prices fully reflect available information and adjust quickly to new data.

Opportunity Costs

The cost of foregoing the next best alternative when making a decision or choice.

Post Hoc, Ergo Propter Hoc

A logical fallacy that suggests that because one event followed another, the first event caused the second.

Inductive Reasoning

the process of making generalizations based on specific observations or instances.