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If F is Defined by F (X) = X2, Find F'(2). - Mathematics

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प्रश्न

If f is defined by f (x) = x2, find f'(2).

थोडक्यात उत्तर
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उत्तर

Given:  

\[f(x) = x^2\]

We know a  polynomial function is everywhere differentiable. Therefore 

\[f(x)\]  is differentiable at 
\[x = 2\]

\[f'(2) = \lim_{h \to 0} \frac{f(2 + h) - f(2)}{h}\]
\[ \Rightarrow f'(2) = \lim_{h \to 0} \frac{(2 + h )^2 - 2^2}{h}\]
\[ \Rightarrow f'(2) = \lim_{h \to 0} \frac{(4 + h^2 + 4h) - 4}{h}\]
\[ \Rightarrow f'(2) = \lim_{h \to 0} \frac{h (h + 4)}{h}\]
\[ \Rightarrow f'(2) = 4\]

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पाठ 10: Differentiability - Exercise 10.2 [पृष्ठ १६]

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आरडी शर्मा Mathematics [English] Class 12
पाठ 10 Differentiability
Exercise 10.2 | Q 1 | पृष्ठ १६

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