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Find the Value of K for Which the Function F (X ) = ( X 2 + 3 X − 10 X − 2 , X ≠ 2 K , X 2 ) is Continuous at X = 2 . - Mathematics

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Question

Find the value of k for which the function f (x ) =  \[\binom{\frac{x^2 + 3x - 10}{x - 2}, x \neq 2}{ k , x^2 }\] is continuous at x = 2 .

 
 
Sum

Solution

Given,

f (x ) =  \[\binom{\frac{x^2 + 3x - 10}{x - 2}, x \neq 2}{ k , x=2 }\]

\[\lim_{x \to 2^-} \left( \frac{x^2 + 3x - 10}{x - 2} \right) = \lim_{x \to 2^-} \left( x + 5 \right) = 7\]

\[f\left( 2 \right) = k\]

\[ \lim_{x \to 2^+} \left( \frac{x^2 + 3x - 10}{x - 2} \right) = \lim_{x \to 2^+} \left( x + 5 \right) = 7\]

If  f ( x)  is continuous at x  = 2 , then

\[\lim_{x \to 2^-} f(x) = f(2) = \lim_{x \to 2^+} f(x)\]
\[\Rightarrow k = 7\]
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Chapter 9: Continuity - Exercise 9.3 [Page 42]

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RD Sharma Mathematics [English] Class 12
Chapter 9 Continuity
Exercise 9.3 | Q 12 | Page 42

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