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Prove that the Function F(X) = Loge X Is Increasing on (0, ∞) ? - Mathematics

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प्रश्न

Prove that the function f(x) = loge x is increasing on (0, ∞) ?

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उत्तर

\[\text { Let } x_1 , x_2 \in \left( 0, \infty \right)\text {  such that } x_1 < x_2 . \text { Then },\]

\[ x_1 < x_2 \]

\[ \Rightarrow \log_e x_1 < \log_e x_2 \]

\[ \Rightarrow f\left( x_1 \right) < f\left( x_2 \right)\]

\[\therefore x_1 < x_2 \Rightarrow f\left( x_1 \right) < f\left( x_2 \right), \forall x_1 , x_2 \in \left( 0, \infty \right)\]

\[\text { So,}f\left( x \right) \text { is increasing on }\left( 0, \infty \right).\]

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अध्याय 17: Increasing and Decreasing Functions - Exercise 17.1 [पृष्ठ १०]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 17 Increasing and Decreasing Functions
Exercise 17.1 | Q 1 | पृष्ठ १०

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