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Question
The function f(x) = tanx – x ______.
Options
Always increases
Always decreases
Never increases
Sometimes increases and sometimes decreases
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Solution
The function f(x) = tanx – x always increases.
Explanation:
Here, f(x) = tan x – x
So, f'(x) = sec2x – 1
f'(x) > 0 ∀ x ∈ R
So f(x) is always increasing.
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