Verify the Given Identity $\cos ( x + y ) \cos ( x - y ) = \cos ^ { 2 } x - \sin ^ { 2 } y$

question 44

Essay

Verify the given identity. $\cos ( x + y ) \cos ( x - y ) = \cos ^ { 2 } x - \sin ^ { 2 } y$

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Definitions:

Technology Advances

Progressive developments and improvements in technology that enhance productivity, efficiency, and the quality of goods and services.

Production Possibilities Curve

A graph that shows the maximum quantity of one good that can be produced for each possible quantity of another good produced, illustrating the trade-offs and opportunity costs of production choices.

Inefficiently

A descriptor for processes or activities that do not use resources in the best possible way, resulting in wasted effort or energy and not achieving maximum productivity.

Economic Growth

Economic growth refers to an increase in the productive capacity of an economy, evidenced by a rise in national income, goods, and services over a period of time.