Читать книгу Probability and Statistical Inference - Robert Bartoszynski - Страница 35
Example 1.16
ОглавлениеLet and be the sets of points on the plane satisfying the conditions and respectively. If , then is a decreasing sequence, and therefore . Since for all if and only if , we have . On the other hand, if , then is an increasing sequence, and . We leave a justification of the last equality to the reader.