How to Prove f(A and B) is in f(A) and f(B) Using Element Argument

JessBrown
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So X, Y = non-empty sets, and f = function (X,Y)

I have to show that

f(A and B) (c underlined) f(A) and f(B)

using element argument.

I have no idea - started with choosing x as a particular but arbitrarily chosen element of f(A and B) so now I have to show it is in f(A) and f(B) but I don't know how! any help would be awesome, thanks!
 
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Hi Jess! :smile:
JessBrown said:
- started with choosing x as a particular but arbitrarily chosen element of f(A and B)

Start with if x ε f(A&B), then ∃ … :wink:
 

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