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Test whether the following functions are increasing or decreasing: f(x) = (1)/x, x ∈ R, x ≠ 0. - Mathematics and Statistics

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प्रश्न

Test whether the following functions are increasing or decreasing: f(x) = `x-(1)/x`, x ∈ R, x ≠ 0.

योग
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उत्तर

`f(x) = x - 1/x`

`f'(x) = d/dx (x-1/x)`

`= 1-(-1/x^2)`

`= 1+1/x^2 > 0` for all x ∈ R, where x ≠ 0 

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अध्याय 2: Applications of Derivatives - Exercise 2.4 [पृष्ठ ८९]

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बालभारती Mathematics and Statistics 2 (Arts and Science) [English] Standard 12 Maharashtra State Board
अध्याय 2 Applications of Derivatives
Exercise 2.4 | Q 1.3 | पृष्ठ ८९

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