FIRST COURSE IN ABSTRACT ALGEBRA
CERTIFICATION EVALUATION TEST COMPLETE
QUESTIONS AND CORRECT ANSWERS
◉ Subset.
Answer: Every Element of A is an element of B: A ⊆ B
◉ Power Set.
Answer: Set of all subsets
◉ Intersection (A ∩ B).
Answer: Elements in A AND in B
◉ Union (A ∪ B).
Answer: Elements in A OR in B
◉ Cartesian Product (A × B).
Answer: {(X,Y) : X ∈ A, Y ∈ B}
◉ Division (A | B).
Answer: let a, b ∈ ℤ and b ≠ 0. Then b *divides* a if ∃k ∈ ℤ s.t. a = k⋅b
, Therefore, b is a divisor of a
◉ Relation.
Answer: between X and Y is a subset of X × Y
◉ Function.
Answer: from X to Y is a relation f between X and Y s.t. each x ∈ X
appears as the first number of *exactly one* ordered pair y = f(x)
Notation:
f: X --> Y
x |--> f(x)
◉ Domain.
Answer: all numbers in 1st set (X)
◉ Codomain.
Answer: all numbers in 2nd set (Y)
◉ Range.
Answer: numbers in Y mapped to a value in X
CERTIFICATION EVALUATION TEST COMPLETE
QUESTIONS AND CORRECT ANSWERS
◉ Subset.
Answer: Every Element of A is an element of B: A ⊆ B
◉ Power Set.
Answer: Set of all subsets
◉ Intersection (A ∩ B).
Answer: Elements in A AND in B
◉ Union (A ∪ B).
Answer: Elements in A OR in B
◉ Cartesian Product (A × B).
Answer: {(X,Y) : X ∈ A, Y ∈ B}
◉ Division (A | B).
Answer: let a, b ∈ ℤ and b ≠ 0. Then b *divides* a if ∃k ∈ ℤ s.t. a = k⋅b
, Therefore, b is a divisor of a
◉ Relation.
Answer: between X and Y is a subset of X × Y
◉ Function.
Answer: from X to Y is a relation f between X and Y s.t. each x ∈ X
appears as the first number of *exactly one* ordered pair y = f(x)
Notation:
f: X --> Y
x |--> f(x)
◉ Domain.
Answer: all numbers in 1st set (X)
◉ Codomain.
Answer: all numbers in 2nd set (Y)
◉ Range.
Answer: numbers in Y mapped to a value in X