Express the Product as a Sum or Difference $$\sin \frac { x } { 2 } \cos \frac { 9 x } { 2 }$$

question 75

Multiple Choice

Express the product as a sum or difference.
- $$\sin \frac { x } { 2 } \cos \frac { 9 x } { 2 }$$

• A) \(\frac { 1 } { 2 } ( \sin 5 x - \sin 4 x )\)
• B) \(\frac { 1 } { 4 } ( \cos 10 x - \sin 8 x )\)
• C) \(\frac { 1 } { 4 } \sin ( \cos 9 x )\)
• D) \(\frac { 1 } { 2 } ( \cos 5 x + \sin 4 x )\)

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Definitions:

Cost Estimates

The projected costs associated with the manufacturing of a product, completion of a project, or provision of a service.

Accountants

Professionals responsible for maintaining and interpreting financial records.

Task Analysis

A systematic process of breaking down a job into its component tasks in order to identify how it can be done effectively.

Costs Estimation

The process of predicting or approximating the cost of completing a project or producing a good.