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

Explanation

Answer is C)
`
f(x)=k x^{3}-9 x^{2}+9 x+3 `is monotonically increasing `forall x in R`
`

f^{prime}(x)=3 k x x^{2}-18 x+9 `
`
=3(k x x^{2}-6 x+3)>0`


for the equation
`
a x^{2}+b x+c to be +ve`
`
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