Question

Let S be the set {(-1)^n +1 - (1/n): all n are natural numbers}. 1. find...

Let S be the set {(-1)^n +1 - (1/n): all n are natural numbers}.

1. find the infimum and the supremum of S, and prove that these are indeed the infimum and supremum.

2. find all the boundary points of the set S. Prove that each of these numbers is a boundary point.

3. Is the set S closed? Compact? give reasons.

4. Complete the sentence: Any nonempty compact set has a....

Homework Answers

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
1. (a) Let S be a nonempty set of real numbers that is bounded above. Prove...
1. (a) Let S be a nonempty set of real numbers that is bounded above. Prove that if u and v are both least upper bounds of S, then u = v. (b) Let a > 0 be a real number. Define S := {1 − a n : n ∈ N}. Prove that if epsilon > 0, then there is an element x ∈ S such that x > 1−epsilon.
Exercise 6.6. Let the inductive set be equal to all natural numbers, N. Prove the following...
Exercise 6.6. Let the inductive set be equal to all natural numbers, N. Prove the following propositions. (a) ∀n, 2n ≥ 1 + n. (b) ∀n, 4n − 1 is divisible by 3. (c) ∀n, 3n ≥ 1 + 2 n. (d) ∀n, 21 + 2 2 + ⋯ + 2 n = 2 n+1 − 2.
A. Let p and r be real numbers, with p < r. Using the axioms of...
A. Let p and r be real numbers, with p < r. Using the axioms of the real number system, prove there exists a real number q so that p < q < r. B. Let f: R→R be a polynomial function of even degree and let A={f(x)|x ∈R} be the range of f. Define f such that it has at least two terms. 1. Using the properties and definitions of the real number system, and in particular the definition...
Let the set N of natural numbers be endowed with the cofinite topology (in which a...
Let the set N of natural numbers be endowed with the cofinite topology (in which a set is open if and only if it is empty or its complement is finite). (a) Is N connected? Justify your answer. (b) Is N compact? Justify your answer. (c) Explain why the function f : N → N, n→ n ^3 is continuous. (d) Exhibit a function g : N → N which is not continuous.
If we let N stand for the set of all natural numbers, then we write 6N...
If we let N stand for the set of all natural numbers, then we write 6N for the set of natural numbers all multiplied by 6 (so 6N = {6, 12, 18, 24, . . . }). Show that the sets N and 6N have the same cardinality by describing an explicit one-to-one correspondence between the two sets.
Find all natural numbers n so that    n3 + (n + 1)3 > (n +...
Find all natural numbers n so that    n3 + (n + 1)3 > (n + 2)3. Prove your result using induction.
Let S(n) be a monotonic non-decreasing positive function defined for all natural numbers n. We do...
Let S(n) be a monotonic non-decreasing positive function defined for all natural numbers n. We do not know the value of S(n) for every n ∈ N except when n = 2k for some k ∈ N, in which case S(n) = n log n + 3n − 5. Show that S(n) ∈ Θ(n log n). Hint: (if you use it, you need to prove it): ∀n > 1 ∈ N, ∃k ∈ N, such that 2k-1 ≤ n ≤...
Let S(n) be a monotonic non-decreasing positive function defined for all natural numbers n. We do...
Let S(n) be a monotonic non-decreasing positive function defined for all natural numbers n. We do not know the value of S(n) for every n ∈ N except when n = 2k for some k ∈ N, in which case S(n) = n log n + 3n − 5. Show that S(n) ∈ Θ(n log n). Hint: (if you use it, you need to prove it): ∀n > 1 ∈ N, ∃k ∈ N, such that 2k-1 ≤ n ≤...
Let S(n) be a monotonic non-decreasing positive function defined for all natural numbers n. We do...
Let S(n) be a monotonic non-decreasing positive function defined for all natural numbers n. We do not know the value of S(n) for every n ∈ N except when n = 2k for some k ∈ N, in which case S(n) = n log n + 3n − 5. Show that S(n) ∈ Θ(n log n). Hint: (if you use it, you need to prove it): ∀n > 1 ∈ N, ∃k ∈ N, such that 2k-1 ≤ n ≤...
For n in natural number, let A_n be the subset of all those real numbers that...
For n in natural number, let A_n be the subset of all those real numbers that are roots of some polynomial of degree n with rational coefficients. Prove: for every n in natural number, A_n is countable.