Talk:Sum of Integrals on Adjacent Intervals for Continuous Functions

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Your final "Comment" section reads like: "If we only had some eggs, we could have ham and eggs, if we only had some ham." --prime mover 18:20, 22 January 2012 (EST)

I do not like green eggs and ham. --GFauxPas 19:07, 22 January 2012 (EST)

I want to create a version of this theorem for complex integrals. My intention is to call the new theorem Sum of Integrals on Adjacent Intervals/Corollary, and write the theorem on a subpage of this page. Or, should I instead call the new theorem Sum of Complex Integrals on Adjacent Intervals? --Anghel (talk) 22:42, 5 December 2012 (UTC)

You could make the latter a redirect to the former, or, which I prefer, put it as a corollary on this page, but do not create it as a subpage, but properly on its own page with the suggested second title. Cf. Definition:Exponential (Category Theory) and Definition:Category with Exponentials. It is my experience that this practice makes web searches on PW more effective. --Lord_Farin (talk) 22:53, 5 December 2012 (UTC)
I disagree - making a subpage has the added advantage that a link to the parent page is available at the top of the page so you can directly go there and view the page in its full context - which you miss if you merely transclude a random page which is not a subpage. --prime mover (talk) 23:05, 5 December 2012 (UTC)
In this case the corollary is a proper generalization; I use this construction sparsely, when I feel an Also see would be too weak an indication of the connection of the results. In general, the construction you advocate is to be the default approach; I'm merely suggesting another approach may have its merit in certain cases. --Lord_Farin (talk) 23:34, 5 December 2012 (UTC)
No worries. Get the page written is the main thing, we can determine the best way to incorporate it into the existing structure in due course. --prime mover (talk) 06:44, 6 December 2012 (UTC)

Continuity

Why would we impose continuity in place of mere Riemann integrability? Same for Sum of Complex Integrals on Adjacent Intervals. --Lord_Farin (talk) 11:15, 8 December 2012 (UTC)

Because the initial page was written based on a child's first guide to analysis. That grown-up stuff about Riemann integrability wasn't covered. --prime mover (talk) 12:40, 8 December 2012 (UTC)
Answer to the second part of the question: Because Sum of Complex Integrals on Adjacent Intervals needed to reference this page in the proof. It isn't a great loss for complex analysists to assume continuitity of the integrable function. In fact, one of my main sources only defines the complex integral for continuous functions. --Anghel (talk) 22:05, 8 December 2012 (UTC)

More Generality

Does anyone know if this site has a version of the more general measure-theoretic version of this statement? I mean the fact that in a measure space $(X,\mu)$, with measurable sets $A \subset E$, and an integrable function $f$, the equality:

$\ds \int_E f \rd \mu = \int_A f \rd \mu + \int_{E \setminus A} f \rd \mu$

If so, what is the page called?

-- Ovenhouse (talk) 23:19, 30 December 2014 (UTC)

I'm pretty confident that it doesn't exist yet, because virtually all general measure theory is taken from Schilling's book, and he glosses over it.
If you can think of a good name, feel free to create the page; the proof is almost instantaneous using an appropriate "linearity for integrals" theorem. — Lord_Farin (talk) 14:20, 31 December 2014 (UTC)
Yeah, Rudin and Royden do the same thing. They skip the proof and say it's immediate. Although, yeah, it follows pretty quickly from using linearity. -- Ovenhouse (talk) 15:35, 31 December 2014 (UTC)