Exercise 3.4.8

Follow these steps to show that the Cantor set is totally disconnected in the sense described in Exercise 3.4.7. Let C = n = 0 C n , as defined in Section 3.1.

(a)
Given x , y C , with x < y , set 𝜖 = y x . For each n = 0 , 1 , 2 , , the set C n consists of a finite number of closed intervals. Explain why there must exist an N large enough so that it is impossible for x and y both to belong to the same closed interval of C N .
(b)
Show that C is totally disconnected.

Answers

(a)
Since the length of every interval goes to zero, we set N large enough that the length of every interval is less then 𝜖 , meaning x and y cannot be in the same interval.
(b)
Obvious
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2022-01-27 00:00
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