Basic Sigma summation , i just don't understand: 2u^2 ( sum[i] (u_i/u) sqrt[s_i] )^2

[Jessias]

Could someone please illustrate how to calculate the attached formula? (See attachment) With a brief explanation, please.
I am mainly confused about how the Sigma (summation) symbol is correctly used.

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. . . . .\(\displaystyle \large{\displaystyle 2u^2\, \left(\sum_{i}\, \dfrac{u_i}{u}\, \sqrt{\strut s_i\,}\right)^2}\)

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Background: This is part of a monster equation I have for a behemoth of an excel spreadsheet which I have had to make for the equation. It seems that the attached part is confusing me and I can't get on with my work (My masters thesis. Not in math , fortunately ) because of it. My results for the spreadsheet seem to hinge on this part of the formula.... which i just don't seem to understand


Many thanks in advance for your help. I would be sooo grateful to have this solved.

 

[Deleted member 4993]

Could someone please illustrate how to calculate the attached formula? (See attachment) With a brief explanation, please.
I am mainly confused about how the Sigma (summation) symbol is correctly used.

---

. . . . .\(\displaystyle \large{\displaystyle 2u^2\, \left(\sum_{i}\, \dfrac{u_i}{u}\, \sqrt{\strut s_i\,}\right)^2}\)

---

Background: This is part of a monster equation I have for a behemoth of an excel spreadsheet which I have had to make for the equation. It seems that the attached part is confusing me and I can't get on with my work (My masters thesis. Not in math , fortunately :grin: ) because of it. My results for the spreadsheet seem to hinge on this part of the formula.... which i just don't seem to understand


Many thanks in advance for your help. I would be sooo grateful to have this solved. :smile:

\(\displaystyle \displaystyle{2u^2\left (\sum_i \frac{u_i}{u}\sqrt{s_i}\right )^2}\)

\(\displaystyle \displaystyle{= 2\left (\sum_i u_i \sqrt{s_i}\right )^2}\)

Then what did you do.....

 

[mmm4444bot]

Could someone please illustrate how to calculate the attached formula?

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. . . . .\(\displaystyle \large{\displaystyle 2u^2\, \left(\sum_{i}\, \dfrac{u_i}{u}\, \sqrt{\strut s_i\,}\right)^2}\)

What are you trying to calculate? The value of the sum?

Are we assuming that the index starts at i = 1?

There's no ending value for i displayed above the sigma symbol. Is this expression an infinite summation?