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Mark the Correct Alternative in the Following Question: Let F : R → R Be Given by F(X) = Tanx. Then, F1(1) is (A) π 4 (B) { N π + π 4 : N ∈ Z } (C) Does Not Exist (D) None of These

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Question

Mark the correct alternative in the following question:

Let f : → R be given by f(x) = tanx. Then, f-1(1) is

 

 

Options

  •  \[\frac{\pi}{4}\]   

  • \[\left\{ n\pi + \frac{\pi}{4}: n \in Z \right\}\]

  • does not exist    

  • none of these

MCQ
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Solution

We have, 

f : R → R is given by 

f (x) = tan x 

⇒ f-1 (x) = tan-1 x

∴ f-1 (1) = tan-1 1 = {nπ + π /4 : n ∈ Z}

Hence, the correct alternative is option (b).

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Chapter 2: Functions - Exercise 2.6 [Page 79]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 2 Functions
Exercise 2.6 | Q 50 | Page 79

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