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Theorem fdmi 5228
Description: The domain of a mapping. (Contributed by set.mm contributors, 28-Jul-2008.)
Hypothesis
Ref Expression
fdmi.1 F:A–→B
Assertion
Ref Expression
fdmi dom F = A

Proof of Theorem fdmi
StepHypRef Expression
1 fdmi.1 . 2 F:A–→B
2 fdm 5227 . 2 (F:A–→B → dom F = A)
31, 2ax-mp 5 1 dom F = A
Colors of variables: wff setvar class
Syntax hints:   = wceq 1642  dom cdm 4773  –→wf 4778
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8
This theorem depends on definitions:  df-bi 177  df-an 360  df-fn 4791  df-f 4792
This theorem is referenced by:  f0cli  5419
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