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What is the Formula of (1 – cos x)/sin x

What is the formula of (1 - cos x)/sin x? Find the answer to this question and access a vast question bank that is customized for students.

Answer: 

Before solving this problem, we will need to know a few formulas such as:

1-cosx= 2sin²(x/2)………………………………………(1)

And,

sin x=2sin(x / 2).cos(x / 2)…………………………(2)

Hence, from (1) and (2), we get

(1-cos x)/sin x = {2sin²(x/2)}/2sin(x/2).cos(x/2)       
 On taking 2sin(x/2) common and cancelling, we get

 (1-cos x)/sin x= sin (x/2)/cos(x/2)

Therefore,  

As sin x/cos x = tan x

Thus,

(1-cos x)/sin x=tan⁡(x / 2)

Hence, it can be concluded that the value of (1-cos x)/sin x is equal to tan (x/2).

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