Shouldn’t boundary points be and element of the given set since boundary points must intersect both the set and the compliment thus making it an element of both the set and its compliment
Hi. Can you confirm if this is correct: Interior: Int(E) = (-1,5) union (10,inf) and since {5,7} excluded, E is not open. Accumulation: Ē = [-1,5] union [10,inf] and since {-1,10} not in E, E is not closed. Boundary: {-1,5,7,10}. Or would it be an interval excluding Int(E) Isolated Point = {7}
This is late, but I don't think you include inf with a bracket. It depends on if you are considering inf as a element of R or a symbol by convention for the concept of infinitely extending. hope that makes sense.
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Shouldn’t boundary points be and element of the given set since boundary points must intersect both the set and the compliment thus making it an element of both the set and its compliment
Hi. Can you confirm if this is correct:
Interior: Int(E) = (-1,5) union (10,inf) and since {5,7} excluded, E is not open.
Accumulation: Ē = [-1,5] union [10,inf] and since {-1,10} not in E, E is not closed.
Boundary: {-1,5,7,10}. Or would it be an interval excluding Int(E)
Isolated Point = {7}
This is late, but I don't think you include inf with a bracket. It depends on if you are considering inf as a element of R or a symbol by convention for the concept of infinitely extending. hope that makes sense.