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If F (X) is Differentiable at X = C, Then Write the Value of Lim X → C F ( X ) - Mathematics

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प्रश्न

If f (x) is differentiable at x = c, then write the value of 

\[\lim_{x \to c} f \left( x \right)\]
संक्षेप में उत्तर
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उत्तर

Given: 

\[f(x)\]  is differentiable at 
\[x = c\]. Then,
\[\lim_{x \to c} \frac{f(x) - f(c)}{x - c}\] exists finitely.
or,   
\[\lim_{x \to c} \frac{f(x) - f(c)}{x - c} = f'(c)\]
Consider,  
\[\lim_{x \to c} f(x) = \lim_{x \to c} \left[ \left\{ \frac{f(x) - f(c)}{x - c} \right\} (x - c) + f(c) \right]\]
\[ \lim_{x \to c} f(x) = \lim_{x \to c} \left[ \left\{ \frac{f(x) - f(c)}{x - c} \right\} (x - c) \right] + f(c)\]
\[ \lim_{x \to c} f(x) = \lim_{x \to c} \left\{ \frac{f(x) - f(c)}{x - c} \right\} \lim_{x \to c} (x - c) + f(c)\]
\[ \lim_{x \to c} f(x) = f'(c) \times 0 + f(c) = f(c)\]
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अध्याय 10: Differentiability - Exercise 10.3 [पृष्ठ १७]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 10 Differentiability
Exercise 10.3 | Q 5 | पृष्ठ १७

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