Which of the following is not equal to cot⁡(210°)? cot⁡(-150°) cot⁡(30°) -cot⁡(30°) -cot⁡(-30°)

Option C

Step-by-step explanation:

Given : cot (210°)

Solution:

Identity :

So,  

So,

Option 1:

Identity :

So,

Now ,

So,

So

Option 2 :

So,

Option 3:

Thus

Option 4:

Identity :

So,

Hence Option C is not equal to

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step-by-step explanation: