Prove $\cos \left( x + \frac { \pi } { 4 } \right) + \cos \left( x - \frac { \pi } { 4 } \right) = \sqrt { 2 } \cos x$

question 39

Essay

Prove $\cos \left( x + \frac { \pi } { 4 } \right) + \cos \left( x - \frac { \pi } { 4 } \right) = \sqrt { 2 } \cos x$ .

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Definitions:

Time Pressure

The stress or urgency to complete tasks or make decisions within a limited timeframe.

Job Demands

are aspects of a job that require sustained physical and psychological effort and are therefore associated with certain physiological and psychological costs.

Organizational Strategies

Comprehensive plans and actions implemented by businesses or organizations to achieve long-term goals and objectives.

Managing Stress

involves strategies and techniques to control and reduce stress levels in oneself or in the workplace to improve well-being and performance.