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

question 98

Essay

Establish 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:

Labor Relations Expert

A professional specializing in handling the relationship between employers and their workers, often dealing with unions and collective bargaining.

Negotiations

The process of discussing terms and conditions between two or more parties to reach a mutual agreement or resolve differences.

Permissive Issue

A permissive issue is a topic or subject matter in negotiations (such as labor negotiations) that can be discussed and possibly agreed upon but is not legally required to be part of the negotiation process.

Collective Bargaining

The process by which employers and the representatives of employees negotiate the terms and conditions of employment.