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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 [itex]f[/itex]is a positive continuous function on [itex][1,0] [/itex].For each natural number[itex]n[/itex] define a new function[itex]F_n [/itex] s.t.
[tex] F_n(x) = \int_0^1 t^ne^{xn}f(t)dt [/tex]
(a) Prove that [itex] lim_{n\to\infty}F_n(x) = 0 [/itex] for all real [itex] x [/itex].
(b) Prove that the above limit is uniform on each bounded interval [itex] [a,b] [/itex].
(c) Determine with proof or counterexample wether or not the limit is uniform on [itex] (-\infty, \infty) [/itex].
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 [itex] f(t) [/itex]for [itex] t\in [0,1] [/itex] and [itex]x[/itex] (still not sure if i have to do the cases where [itex] x [/itex] is neg/pos) and then show that the limit is independent of [itex]x[/itex] and [itex]t[/itex], 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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