The sequence $f_n '$ converge to a function $g$ on $[0,1]$ and $f'(x) = g(x), x \in (0,1), f'(1) \neq g'(1)$.

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Let $f_n(x) = \frac{x^n}{n}, 0 \leq x \leq1$. Then

$1) $ the sequence $f_n$ converge uniformly to a function $f$ on $[0,1]$.

$2)$ the sequence $f_n '$ converge to a function $g$ on $[0,1]$ and $f'(x) = g(x), x \in (0,1), f'(1) \neq g'(1)$.

I have done the first part. i.e. the sequence $f_n$ converge uniformly to a function $f(x) = 0$ on $[0,1]$. I am stuck with the second part.

Here $f_n '(x) = x^{n-1}$ Thus $lim_{n \to \infty} x^{n-1} = 0$.

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If $x=1$, then $f'_n(x) = 1 \to_{n \to \infty} 1$.

If $0$ $\le$ $ x < 1$, then $f'_n(x) \to_{n \to \infty} 0$.

Thus:

$$f'_n(x) \to g(x) = \begin{cases} 0, \text{if $0\le x < 1$} \\ 1, \text{if $x = 1$} \end{cases}$$