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If f(x)=k x^3-9x^2+9x+3 monotonically in...

If `f(x)=k x^3-9x^2+9x+3` monotonically increasing in `R ,` then `k<3` (b) `klt=2` `kgeq3` (d) none of these

A

`klt3`

B

`kle2`

C

`kge3`

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
3
`f(x) = 3kx^(2)-18x+9=3 [kx^(2)-6x+3]ge0`
or `D=b^(2)-4aclt0,kgt0 i.e 36-12kle0`
or `kge3`
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CENGAGE-MONOTONICITY AND MAXIMA MINIMA OF FUNCTIONS-Exercise (Single)
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