A) \[k<3\]
B) \[k\le 3\]
C) \[k>3\]
D) None of these
Correct Answer: C
Solution :
\[f'(x)=3k{{x}^{2}}-18x+9=3\,\,[k{{x}^{2}}-6x+3]>0,\,\,\forall x\in R\] \[\therefore \Delta ={{b}^{2}}-4ac<0\,\,\,,k>0\] \[i.e.,\ \ 36-12k<0\]or \[k>3\].You need to login to perform this action.
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