Mark the correct alternative in the following:

The function f(x) = x9 + 3x7 + 64 is increasing on


Formula:- (i) The necessary and sufficient condition for differentiable function defined on (a,b) to be strictly increasing on (a, b) is that f’(x)>0 for all x(a,b)


Given:-


f(x) = x9 + 3x7 + 64



For increasing f’(x)>o


9x8+21x6>0


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