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Let F : R → R Be Given by F ( X ) = X 2 − 3 Then, F − 1 is Given by (A) √ X + 3 (B) √ X + 3 (C) X + √ 3 (D) None of These - Mathematics

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Question

Let 
\[f : R \to R\]  be given by \[f\left( x \right) = x^2 - 3\] Then, \[f^{- 1}\] is given by 

 

Options

  • \[\sqrt{x + 3}\]

  • \[\sqrt{x} + 3\]

  •  \[x + \sqrt{3}\]

  • None of these

MCQ
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Solution

(d) 

\[\text{Let} f^{- 1} \left( x \right) = y\] 
\[f\left( y \right) = x\] 
\[ y^2 - 3 = x\] 
\[ y^2 = x + 3\] 
\[y = \pm \sqrt{x + 3}\]

So, the answer is (d).

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Chapter 2: Functions - Exercise 2.6 [Page 78]

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RD Sharma Mathematics [English] Class 12
Chapter 2 Functions
Exercise 2.6 | Q 49 | Page 78

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