Q3 of 105 Page 17

Mark the correct alternative in the following:

The function f(x) = xx decreases on the interval.


Formula:- 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) = xx



now for decreasing


f’(x)<0


xx(1+logx)<0


(1+logx)<0


logx<-1


x<e-1


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