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At x = 4 the functionf (x) = 2 log (x - ...

At x = 4 the function`f (x) = 2 log (x - 2) - x^2 + 4x +1` is

A

Increasing

B

Decreasing

C

Neither increasing nor decreasing

D

None

Text Solution

Verified by Experts

The correct Answer is:
B
Given,`f(x)=2log(x−2)−x^2+4x+1 `
f(x) is valid when x>2
`f'(x)=2/(x-2)-2(x-2)`
now for f′(x)>0
since, x>2
therefore,` 1−(x−2)^2>0`
. ⇒`(x−3)(x−1)<0` and `x>2. `
...
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