SOLUTION: Let A be a finite set, and define by f: P(B) -> N(non-negative integers) by f(B) = |B|. That is, f takes a subset of A as an input and outputs the cardinality of that sub

Question 1065734: Let A be a finite set, and define by f: P(B) -> N(non-negative integers) by f(B) = |B|.
That is, f takes a subset of A as an input and outputs the cardinality of that subset.
a) Is f injective? Prove your answer.
b) Is f surjective? Prove your answer.

Answer by ikleyn(52873) (Show Source): You can put this solution on YOUR website!
.
You MUST define "who is B" and "who is P" to make your formulation correct.

I am not going to make this job instead of you.

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I perfectly understand what you were going to say, but, for educational purposes, want you make your writing correct.

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