fluidistic
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Homework Statement
Almost like the title says : Let [tex]f_n (x)=x^n[/tex] for [tex]0 \leq x \leq 1[/tex]. Find the pointwise limit of [tex]f_n[/tex] and show that the convergence is not uniform.
What happens if [tex]x \in [0,1)[/tex]?
2. The attempt at a solution
[tex]\lim _{n \to \infty} f_n = \lim _{n \to \infty} x^n = 0[/tex] if [tex]x[/tex] is strictly lesser than [tex]1[/tex] and it's worth [tex]1[/tex] if [tex]x[/tex] equals [tex]1[/tex]. (I wonder if I have to prove it via the definition of limits).
I don't have much ideas about the non uniform convergence. Checking up some wikipedia, I think that if I can show that if [tex]a_n[/tex] does not tend to [tex]0[/tex] when [tex]n[/tex] tends to [tex]\infty[/tex], I'm done. Where [tex]a_n=sup |f_n (x)-f(x)|[/tex].
I get that [tex]a_n = sup |x(x^{n-1}-1)|[/tex] but I think it's worth [tex]0[/tex], hence implying the uniform convergence of [tex]f_n[/tex]...
Answering the last question : By intuition the convergence is uniform.