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Determine the Value of the Constant K So that the Function F ( X ) = { X 2 − 3 X + 2 X − 1 , I F X ≠ 1 K , I F X = 1 is Continuous at X = 1 - Mathematics

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Question

Determine the value of the constant k so that the function 

\[f\left( x \right) = \left\{ \begin{array}{l}\frac{x^2 - 3x + 2}{x - 1}, if & x \neq 1 \\ k , if & x = 1\end{array}\text{is continuous at x} = 1 \right.\] 

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Solution

Given: 

\[f\left( x \right) = \binom{\frac{x^2 - 3x + 2}{x - 1}, if x \neq 1}{k, if x = 1}\]

If

\[f\left( x \right)\]is continuous at x = 1, then,

\[\lim_{x \to 1} f\left( x \right) = f\left( 1 \right)\]

\[\lim_{x \to 1} \frac{x^2 - 3x + 2}{x - 1} = k\]

\[\lim_{x \to 1} \frac{\left( x - 2 \right)\left( x - 1 \right)}{x - 1} = k\]

\[\lim_{x \to 1} \left( x - 2 \right) = k\]

\[k = - 1\]

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Chapter 9: Continuity - Exercise 9.1 [Page 18]

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RD Sharma Mathematics [English] Class 12
Chapter 9 Continuity
Exercise 9.1 | Q 19 | Page 18

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