推 plover :(b) In R^1, define E_r = [r,∞). 03/11 13:06
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◆ From: 163.24.78.119
Given a Lebesgue measurable subset A of R^n, we denote
by │A│ the Lebesgue measure of A. Assume that {E_r:r屬於N}
is a decreasing sequence of measurable subsets of R^n so
that E_μ1包含E_ν whenever μ≦ν. We define ε=∩E_r, r€N.
(a) Suppose that │E_r│ is finite for some r屬於N. Prove
that │ε│=lim r→+∞│E_r│
(b) Suppose that the equality │ε│=lim r→+∞│E_r│
could be wrong when │E_r│=∞, for any r屬於N.
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