
derivative proof
show that if the second derivative of function f is greated than zero in the interval [a,b] then the first derivative of function f has atmost one zero in[a,b].and what iff the second derivative of function f is less than 0 throughout [a,b] instead
in the proof do we have to generalise the ppolynomial or do directly by graph
please help

Re: derivative proof
If the derivative of a function is greater than zero, then it is an increasing function, so it can cross the xaxis at most once. In this case, the function is f'(x).
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