Suppose f is a differential function for which limit as x-> infinity f(x) and limit x->infinity f'(x) both exists and are finite. Which of the following must be true?(adsbygoogle = window.adsbygoogle || []).push({});

A. limit x-> infinity f'(x) = 0.

B. limit x0> infinity f''(x) = 0

C. limit x-> infinity f'(x) = limit x-> infinity f'(x)

D. f is a constant function

E. f' is a constant function

The answer is A. Why are the others wrong (especially explaining why B. is wrong)? Can you provide more formal reason other than it is just intuitive?

Thanks!!

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# Differential function for which limit as x-> infinity

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