Prove $\cot \left( x + \frac { \pi } { 4 } \right) = \frac { 1 - \tan x } { \tan x + 1 }$

question 109

Essay

Prove $\cot \left( x + \frac { \pi } { 4 } \right) = \frac { 1 - \tan x } { \tan x + 1 }$ .

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Definitions:

Online Retailing

B2C electronic commerce in which individual consumers directly buy goods or services over the Internet; also known as e-retailing.

E-Retailing

The selling of goods and services through online platforms, also known as electronic retailing, encompassing a wide range of online business models.

Cyber-Retailing

The activity of selling products or services through electronic means, such as the internet, rather than through a physical retail store.

Department Stores

Merchandise outlets that carry a wide variety of product lines, with each line operated as a separate department and managed by specialist merchandisers and buyers.