# Let A and B be non empty sets. Consider the function f: AxB -> A given by f(a,b) = a. When is f surjective? When is f injective? Prove?

• Let A and B be non empty sets. Consider the function f: AxB -> A given by f(a,b) = a. When is f surjective? When is f injective? Prove?

Let A and B be non empty sets. Consider the function f: AxB -> A given by f(a,b) ... When is f surjective? When is f injective? Prove?
Positive: 88 %
The function f is surjective (onto) if f(A) = B. ... Theorem 1 Let f : A → B and g : ... inﬁnite, and countable sets • The empty set ∅ has zero ...
Positive: 85 %

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Note that the terms “surjective” and “injective” are ... For possibly empty words u and v, we consider ... Let S be a semigroup. For a,b ...
Positive: 88 %
To show a function f:B->C is surjective you must start by saying "Let ... HOW TO PROVE f:B->C IS SURJECTIVE: Let x in C. : : ... given 2. Let a,b in T 3 ...
Positive: 83 %
Let A and B be sets and let ?A and ?B be the projections from AxB ... (b) A continuous function f[a; b] ... Is the trace function injective? Is it surjective?