Rudin book's, Real and complex analysis chapter 6.
Of (1) every rearrangement of series must also converge.
My questiion is: Why concludes that $\mu(E)$ converges absolutely?
Thank you all.
Rudin book's, Real and complex analysis chapter 6.
Of (1) every rearrangement of series must also converge.
My questiion is: Why concludes that $\mu(E)$ converges absolutely?
Thank you all.
Theore 3.56 that you've cited seems to prove another direction. Perhaps, here we rather shall use Riemann rearrangement theorem. Notice that in your case, not only every rearrangement converges, they all do converge to the same limit $\mu(E)$. If the series were not absolutely convergent, then there would exist two rearrangements with different limits.