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Show that f(x) = e2x is increasing on R.

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Show that f(x) = e2x is increasing on R.

Show that the function given by f (x) = e 2x is increasing on R.

Sum
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Solution 1

\[f\left( x \right) = e^{2x} \]

\[f'\left( x \right) = 2 e^{2x} \]

\[\text { Now,} \]

\[x \in R\]

 Since the value of   `e^{2x}` text  is always positive for any real value of x, ` e^{2x}` > 0 . 

\[ \Rightarrow 2 e^{2x} > 0\]

\[ \Rightarrow f'\left( x \right) > 0\]

\[\text { So,f(x)is increasing on R} .\]

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Solution 2

We have f(x) = e2x

f'(x) = 2e2x > 0, x `in` R

f is strictly increasing on R

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Chapter 16: Increasing and Decreasing Functions - Exercise 17.2 [Page 34]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 16 Increasing and Decreasing Functions
Exercise 17.2 | Q 4 | Page 34

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