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The function f(x) = `x - 1/x`, x ∈ R, x ≠ 0 is increasing

#### Options

True

False

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#### Solution

This Statement is **True.**

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**Solution: **f(x) = 2x^{3} – 15x^{2} – 84x – 7

∴ f'(x) = `square`

∴ f'(x) = 6`(square) (square)`

Since f(x) is decreasing function.

∴ f'(x) < 0

**Case 1:** `(square)` > 0 and (x + 2) < 0

∴ x ∈ `square`

**Case 2:** `(square)` < 0 and (x + 2) > 0

∴ x ∈ `square`

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