Question on riemann sum $\lim_{n\rightarrow \infty}\frac{1}{n}\sum_{k=0}^{n}f(\frac{k}{n})$ NBHM $2005$

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Question is to evaluate $$\lim_{n\rightarrow \infty}\frac{1}{n}\sum_{k=0}^{n}f(\frac{k}{n})$$

I see that this is to be done with Riemann sums..

I first partition $[0,1]$ as $\{0,\frac{1}{n},\frac{2}{n},\dots,1\}$

Now, Riemann Sum is defined as $\sum_{i=1}^n f(x^*_i)|(x_i-x_{i-1})|$

So, here i would have

$$f(0).\frac{1}{n}+f(\frac{1}{n})\frac{1}{n}+f(\frac{2}{n})\frac{1}{n}+\dots+f(\frac{n-1}{n})\frac{1}{n}=\frac{1}{n}.\sum_{k=0}^{n-1}f(\frac{k}{n})$$

Or

$$f(\frac{1}{n})\frac{1}{n}+f(\frac{2}{n})\frac{1}{n}+\dots+f(1)\frac{1}{n}\frac{1}{n}.\sum_{k=1}^{n}f(\frac{k}{n})$$

I would get first case if i take $x^*_i=x_{i-1}$ and i would get second case if i take $x^*_i=x_i$

But I am afraid I would not get $$\frac{1}{n}\sum_{k=0}^{n}f(\frac{k}{n})$$

I am actually confused..

Should the question be something like $$\lim_{n\rightarrow \infty}\frac{1}{n}\sum_{k=0}^{n-1}f(\frac{k}{n})$$?

I am sure i am missing something..

Please help me to clear that.

Thank you