Category:Riemann-Stieltjes Integral

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This category contains results about Riemann-Stieltjes Integral.
Definitions specific to this category can be found in Definitions/Riemann-Stieltjes Integral.

Let $\Bbb I = \closedint a b$ be a closed real interval.

Let $f, \alpha : \Bbb I \to \R$ be a real functions that are bounded on $\Bbb I$.



Then, $f$ is Riemann-Stieltjes integrable with respect to $\alpha$ on $\closedint a b$ if and only if:

there exists some $A \in \R$ such that, for every $\epsilon > 0$, there is a finite subdivision $P_\epsilon$ of $\Bbb I$ such that:
for every Riemann-Stieltjes sum $\map S {P, f, \alpha}$ of $f$ with respect to $\alpha$ for a subdivision $P$, where $P$ is finer than $P_\epsilon$:
$\size {\map S {P, f, \alpha} - A} < \epsilon$

The real number $A$ is called the Riemann-Stieltjes integral of $f$ with respect to $\alpha$ on $\closedint a b$, and is denoted:

$\ds A = \int_a^b f \rd \alpha = \int_a^b \map f x \rd \map \alpha x$