Prove the Identity $$\cos ^ { 2 } x - \sin ^ { 2 } x = 1 - 2 \sin ^ { 2 } x$$

question 311

Essay

Prove the identity.
- $$\cos ^ { 2 } x - \sin ^ { 2 } x = 1 - 2 \sin ^ { 2 } x$$

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Definitions:

Direct Labor-Hours

The total hours worked directly on the production of goods.

Manufacturing Overhead

All indirect costs associated with the production process, including costs related to factory operation but not directly traceable to the product, such as maintenance and utilities.

Work in Process

Inventory that is in the production process but is not yet completed.

Overapplied

A situation where the allocated amount of indirect costs exceeds the actual amount incurred.