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Is Every Continuous Function Differentiable? - Mathematics

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प्रश्न

Is every continuous function differentiable?

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उत्तर

No, function may be continuous at a point but may not be differentiable at that point .
For example: function  

\[f(x) = |x|\]  is continuous at 
 
\[x = 0\]  but it is not differentiable at 
\[x = 0\]
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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 3 | पृष्ठ १७

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संबंधित प्रश्न

A function f(x) is defined as 

\[f\left( x \right) = \begin{cases}\frac{x^2 - 9}{x - 3}; if & x \neq 3 \\ 6 ; if & x = 3\end{cases}\]

Show that f(x) is continuous at x = 3

 

Discuss the continuity of the following functions at the indicated point(s): 

\[f\left( x \right) = \left\{ \begin{array}{l}(x - a)\sin\left( \frac{1}{x - a} \right), & x \neq a \\ 0 , & x = a\end{array}at x = a \right.\]

 


For what value of k is the function 

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Find the value of k for which \[f\left( x \right) = \begin{cases}\frac{1 - \cos 4x}{8 x^2}, \text{ when}  & x \neq 0 \\ k ,\text{ when }  & x = 0\end{cases}\] is continuous at x = 0;

 


In each of the following, find the value of the constant k so that the given function is continuous at the indicated point;  \[f\left( x \right) = \begin{cases}\frac{x^2 - 25}{x - 5}, & x \neq 5 \\ k , & x = 5\end{cases}\]at x = 5


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If \[f\left( x \right) = \left| \log_{10} x \right|\] then at x = 1


Let  \[f\left( x \right) = \begin{cases}\frac{x^4 - 5 x^2 + 4}{\left| \left( x - 1 \right) \left( x - 2 \right) \right|}, & x \neq 1, 2 \\ 6 , & x = 1 \\ 12 , & x = 2\end{cases}\]. Then, f (x) is continuous on the set

 


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