How do I figure out the upper and lower bounds for a riemann sum?

Question

This question I'm working on tells me to assume:

Δx=2π/n and x_i=iΔx

and then gives me:

n b
lim ∑ sinx_iΔx = ∫f(x)dx
n⟶∞ i=1 a

Now I'm pretty sure f(x)=sinx, but I don't know how to find a or b. Sorry if this is a little convoluted, it's hard to type it out. Any help here would be appreciated. Thank you

Answer 1

You just have to figure out how many intervals you want to use (n).

Then, as it says, the interval width is Δx=2π/n

The interval is apparently [0,2π]