Understanding Riemann Sums and Limits | Homework #16 Question

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Homework Statement


Question regarding #16

III-16.jpg



Homework Equations



Riemman Sum

The Attempt at a Solution



I know that the limit of the Riemman Sum is basically the integral. However, I do not know where to go from there. Do I need to use the Summation formulas? Thanks
 
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can you write down the expression for a Riemann integral. something like:

\int_a^b f(x) dx = \lim_{N \to \infty} \sum_{n=1}^N ?

what goes in the question marks?

also, even though Riemann doesn't, assume things in the ? are equally spaced. that's usually good enough.
 
Last edited:
rbj said:
can you write down the expression for a Riemann integral. something like:

\int_a^b f(x) dx = \lim_{N \to \infty} \sum_{n=1}^N ?

what goes in the question marks?

also, even though Riemann doesn't, assume things in the ? are equally spaced. that's usually good enough.

Well, here's what I have so far:

\int_a^b f(x) dx = \lim_{N \to \infty} \sum_{n=1}^N (\frac{1}{N}\sin(\frac{\pi i}{N})
 
So what part of that sum is dx and what part is f(x)? After you know f(x), what is its integral?
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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