Verify the Identity $$\left( 1 + \tan ^ { 2 } u \right) \left( 1 - \sin ^ { 2 } u \right) = 1$$

question 200

Essay

Verify the identity.
- $$\left( 1 + \tan ^ { 2 } u \right) \left( 1 - \sin ^ { 2 } u \right) = 1$$

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Definitions:

Psychological Fatigue

A state of mental exhaustion caused by prolonged cognitive activity, stress, or emotional strain, leading to decreased performance and motivation.

Energy Depletion

The reduction of available energy resources or an individual's physical and mental resources, leading to fatigue or resource scarcity.

Stressful Activities

Tasks or events that induce stress, requiring coping mechanisms to manage mental, emotional, or physical strain.

Aerobic Exercise

Physical activity that improves the efficiency of the cardiovascular system by increasing heart rate and promoting oxygen consumption across the body.