Metamath Proof Explorer


Theorem bnj1307

Description: Technical lemma for bnj60 . This lemma may no longer be used or have become an indirect lemma of the theorem in question (i.e. a lemma of a lemma... of the theorem). (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

Ref Expression
Hypotheses bnj1307.1 C = f | d B f Fn d x d f x = G Y
bnj1307.2 w B x w B
Assertion bnj1307 w C x w C

Proof

Step Hyp Ref Expression
1 bnj1307.1 C = f | d B f Fn d x d f x = G Y
2 bnj1307.2 w B x w B
3 2 nfcii _ x B
4 nfv x f Fn d
5 nfra1 x x d f x = G Y
6 4 5 nfan x f Fn d x d f x = G Y
7 3 6 nfrex x d B f Fn d x d f x = G Y
8 7 nfab _ x f | d B f Fn d x d f x = G Y
9 1 8 nfcxfr _ x C
10 9 nfcrii w C x w C