In: Advanced Math
Problem 3. Consider the unit interval [0, 1], and let ξ be fixed real number with ξ ∈ (0, 1) (note that the case ξ = 1/3 corresponds to the regular Cantor set we learned in our lectures). In stage 1 of the construction, remove the centrally situated open interval in [0, 1] of length ξ. In stage 2 remove the centrally situated open intervals each of relative length ξ (i.e. if the interval has length a you remove an interval of length ξ × a), one in each of the remaining intervals after stage 1, and so on. Let Cξ denote the set which remains after applying the above procedure indefinitely
(a) Prove that Cξ is compact.
(b) Prove that Cξ is totally disconnected and perfect.
(c) Atually, prove that the complement of Cξ in [0, 1] is the union of open intervals of total length equal to 1.
(d) Show directly that m∗(Cξ) = 0.