- #1

Uiiop

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## Homework Statement

Find ∪i=0Ai (with infinite symbol) and ∩ i=0Ai (with infinite symbol) in each of the cases when for each natural number

i, Ai is defined as:

1. Ai = {i,−i, i + 1,−(i + 1), i + 2,−(i + 2), . . .}

2. Ai = {0, i, 2i}

3. Ai = {x : x is a real number such that i < x < i + 1}

4. Ai = {x : x is a real number strictly between − i and i}.

## Homework Equations

## The Attempt at a Solution

I really have no clue on this part of set theory