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Question

Math 6210 • Real Analysis

Fall 1994 • Question 1

Let \(\mathcal F=\{f_\alpha \}_{\alpha \in A}\) be a family of continuous complex valued functions on a compact Hausdorff space. Let \(\{c_\alpha \}_{\alpha \in A}\) be a family of complex numbers. Suppose that for each \(F\subset A\) with \(F\) finite, there exists a complex measure \(\mu _F\) of total variation one on \(X\) such that \[ \int _X f_\alpha \,d\mu _F=c_\alpha \qquad (\forall \alpha \in F). \] Show that there exists a complex measure \(\mu \) on \(X\) of total variation at most one such that \[ \int _X f_\alpha \,d\mu =c_\alpha \qquad (\forall \alpha \in A). \]

Raw LaTeX

Let \(\mathcal F=\{f_\alpha\}_{\alpha\in A}\) be a family of
continuous complex valued functions on a compact Hausdorff space. Let
\(\{c_\alpha\}_{\alpha\in A}\) be a family of complex numbers. Suppose that for
each \(F\subset A\) with \(F\) finite, there exists a complex measure \(\mu_F\) of
total variation one on \(X\) such that
\[
\int_X f_\alpha\,d\mu_F=c_\alpha\qquad(\forall\alpha\in F).
\]
Show that there exists a complex measure \(\mu\) on \(X\) of total variation at most
one such that
\[
\int_X f_\alpha\,d\mu=c_\alpha\qquad(\forall\alpha\in A).
\]