(1). Let {?n} be a Cauchy sequence in a metric spaces X and let {?n} be another sequence in X such that ? (?n, ?n) < 1/n ??? ????? ? ∈ ℕ. Show that {?n} is also a Cauchy sequence in X.
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(1). Let {?n} be a Cauchy sequence in a metric spaces X and let {?n} be...
Show that, if an ≥ 0 for all n ∈ N and (an) is a Cauchy
sequence, then (√ an) is also a Cauchy sequence. Hint: x − y = (√ x
− √y)(√ x + √y)
Show that, if an > 0 for all n є N and (an) is a Cauchy sequence, then (Van) is also a Cauchy sequence. Hint: r -y- (V1-vu) (Va + vⓙ
Show that, if an > 0 for all n є N and...
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Let (X, dx), (Y, dy) be metric spaces and fn be a sequence of functions fn: XY Prove that if {fn} converges uniformly on X then for any a є x lim lim fn()- lim lim /) xa n-00
Problem 1. Let (X, d) be a metric space and t the metric topology on X. (a) Fix a E X. Prove that the map f :(X, T) + R defined by f(x) = d(a, x) is continuous. (b) If {x'n} and {yn} are Cauchy sequences, prove that {d(In, Yn)} is a Cauchy sequence in R.
Exercise 5 (based on Tao). Let (X,d) be an arbitrary metric space. Prove the following statements (1) If a sequence is convergent in X, all its subsequences are converging to the same limit as the original sequence. (2) If a subsequence of a Cauchy sequence is convergent, then the whole sequence is convergent to the same limit as the subsequence. (3) Suppose that (X,d) is complete and Y S X is closed in (X,d). Then the space (Y,dlyxy) is complete....
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please explain the steps you take
2. Let M be the set of all measurable sets in R, and let d be our semi-metric, show that (M, d) is complete: If (An)1 is a Cauchy sequence (with our semi- metric d) then there is a measurable set A EM such that lim, too d(An, A) 0.
2. Let M be the set of all measurable sets in R, and let d be our semi-metric, show that (M, d) is complete:...
3. (a) Let (X, dx), (Y, dy) be two metric spaces, C C X connected, and f : X+Y continuous. Show that f(C) CY is connected.
Problem 2: For any x, y e R let d(x,y):-arctan(y) - arctan(x). Do the following: (1) Prove that d is a metric on R. (2) Letting xnn, prove that {xnJnE is a Cauchy sequence with no limit in R (Note that {xn)nen is NOT Cauchy under the Euclidean metric and that all Cauchy sequences in the Euclidean metric have a limit in R.)
Problem 2: For any x, y e R let d(x,y):-arctan(y) - arctan(x). Do the following: (1) Prove...
9. Let X and Y be metric spaces, and let D be a dense subset of X. (For the definition of "dense, see Problem 4 at the end of Section 3.5.) (a) Let f : X → Y and g : X → Y be continuous functions. Suppose that f(d)gld) for all d E D. Prove that f and g are the same function.