Prove the Identity $$\tan 6 u \tan 4 u = \frac { \tan ^ { 2 } 5 u - \tan ^ { 2 } u } { 1 - \tan ^ { 2 } 5 u \tan ^ { 2 } u }$$

question 146

Essay

Prove the identity.
- $$\tan 6 u \tan 4 u = \frac { \tan ^ { 2 } 5 u - \tan ^ { 2 } u } { 1 - \tan ^ { 2 } 5 u \tan ^ { 2 } u }$$

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Tension

The state of being stretched tight or experiencing mental or emotional strain.

Intrinsically Motivated

Being driven by internal rewards, such as personal satisfaction or the joy of doing something for its own sake.

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Motivation driven by external rewards such as money, fame, grades, and praise, rather than for the sake of the activity itself.

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Having the necessary ability, knowledge, or skill to do something successfully or efficiently.