Prove the Identity $$\cot ( x + y ) \cot ( x - y ) = \frac { 1 - \tan ^ { 2 } x \tan ^ { 2 } y } { \tan ^ { 2 } x - \tan ^ { 2 } y }$$

question 151

Essay

Prove the identity.
- $$\cot ( x + y ) \cot ( x - y ) = \frac { 1 - \tan ^ { 2 } x \tan ^ { 2 } y } { \tan ^ { 2 } x - \tan ^ { 2 } y }$$

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Definitions:

Acrostic

A made-up sentence in which the first letter of each word stands for something.

Order of Operations

A set of rules that determines the sequence in which mathematical operations should be performed to accurately solve expressions.

Vitruvian Man

A drawing by Leonardo da Vinci illustrating the ideal human body proportions based on the writings of the ancient Roman architect Vitruvius.

Method-Of-Place Technique

Also known as the loci method, a mnemonic strategy using visualization of familiar spatial environments to recall information.