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Theorem nfimOLD 1814
Description: If is not free in and , it is not free in . (Contributed by Mario Carneiro, 11-Aug-2016.) (Proof modification is discouraged.) (New usage is discouraged.)
Hypotheses
Ref Expression
nfim.1  F/
nfim.2  F/
Assertion
Ref Expression
nfimOLD  F/

Proof of Theorem nfimOLD
StepHypRef Expression
1 nfim.1 . . . 4  F/
21a1i 10 . . 3  F/
3 nfim.2 . . . 4  F/
43a1i 10 . . 3  F/
52, 4nfimd 1808 . 2  F/
65trud 1323 1  F/
Colors of variables: wff setvar class
Syntax hints:   wi 4   wtru 1316   F/wnf 1544
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-11 1746
This theorem depends on definitions:  df-bi 177  df-tru 1319  df-ex 1542  df-nf 1545
This theorem is referenced by: (None)
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