Bacle H
Posts:
283
Registered:
4/8/12


Re: Does this imply that lim x > oo f'(x) = 0?
Posted:
May 26, 2013 1:25 AM


On Friday, May 24, 2013 8:28:07 PM UTC7, Graham Cooper wrote: > On May 25, 12:50 pm, William Elliot <ma...@panix.com> wrote: > > > On Fri, 24 May 2013, baclesb...@gmail.com wrote: > > > > On Friday, May 24, 2013 3:28:09 AM UTC4, William Elliot wrote: > > > > > > > Suppose f:[0, oo) > R is increasing, differentiable and has a > > > > > > > finite limit as x > oo. Then, must we have lim x > oo f'(x) = > > > > > > > 0? I guess not, but couldn't find a counter example. > > > > How about this: with the same lay out as before: f(n+1)f(n)=f'(cn). > > > > > > Give it up, counter examples have been presented.
Maybe you should check your counterexamples more carefully. > > > > I think this one works.. > > > > 1/(5+sin(x))/x/x > > > > > > http://www.wolframalpha.com/input/?i=1%2F%285%2Bsin%28x%29%29%2Fx%2Fx > > > > > > > > > > Herc > >  > > www.BLoCKPROLOG.com

