Can anyone explain why $(b,a)=(1,0)$ where $b-a=1$.
$\lim_{n\to \infty}(\frac{1}{n+1} +\frac{1}{n+2} +...+\frac{1}{n+n})=\lim_{n\to \infty}\frac{1}{n}\sum_{i=1}^n \frac{1}{1+i/n}=\int_a^b \frac{dx}{1+x}.$
How to determine $a$ and $b $ ?
According to book $b=1$ and $a=0$.