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The Value of K Which Makes F ( X ) = { Sin 1 X , X ≠ 0 K , X = 0 Continuous at X = 0, is (A) 8 (B) 1 (C) −1 (D) None of These - Mathematics

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Question

The value of k which makes \[f\left( x \right) = \begin{cases}\sin\frac{1}{x}, & x \neq 0 \\ k , & x = 0\end{cases}\]    continuous at x = 0, is

 

Options

  • 8

  • 1

  • −1

  • none of these

MCQ
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Solution

 none of these 

If   \[f\left( x \right)\]  is continuous at \[x = 0\] , then 

\[\lim_{x \to 0} f\left( x \right) = f\left( 0 \right)\]
\[ \Rightarrow \lim_{x \to 0} \left( \sin\frac{1}{x} \right) = k\]
\[ \text{ [But} \lim_{x \to 0} \left( \sin\frac{1}{x} \right) \text{ does not exist . Thus, there does not exist any k that makes }  f\left( x \right) \text{ a continuous function .} \]

 

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Chapter 9: Continuity - Exercise 9.4 [Page 46]

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RD Sharma Mathematics [English] Class 12
Chapter 9 Continuity
Exercise 9.4 | Q 36 | Page 46

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