Uniformly continuous function (sequence)

angst18
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Homework Statement


(This is my first post and I'm not sure why the Tex code isn't working, sorry).Suppose fis a positive continuous function on [1,0].For each natural numbern define a new functionF_n s.t.
F_n(x) = \int_0^1 t^ne^{xn}f(t)dt

(a) Prove that lim_{n\to\infty}F_n(x) = 0 for all real x.
(b) Prove that the above limit is uniform on each bounded interval [a,b].
(c) Determine with proof or counterexample wether or not the limit is uniform on (-\infty, \infty).

Homework Equations


The Attempt at a Solution



So, I know that what I'm supposed to do for part (a) is to show that the limit is uniform so that I can bring it into the integrand and evaluate. I even know how to do this in when there's only one variable, but the addition of a 't' as well as an 'x' has me stymied.
I know I'm supposed to fix f(t)for t\in [0,1] and x (still not sure if i have to do the cases where x is neg/pos) and then show that the limit is independent of x and t, but there's something I'm not getting, or I'm doing it in the wrong order, because I'm basically totally stuck.
Thanks in advance for any help.
 
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Hello angst18. Welcome to PF.

To get Tex to work:

After selecting "Preview Post", you need to click on your browser's "Refresh" button. Otherwise the display will not show the updated Tex image. Apparently some memory location doesn't get updated unless you do this.
 
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