Metamath Proof Explorer


Theorem bnj1514

Description: Technical lemma for bnj1500 . 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 bnj1514.1 B = d | d A x d pred x A R d
bnj1514.2 Y = x f pred x A R
bnj1514.3 C = f | d B f Fn d x d f x = G Y
Assertion bnj1514 f C x dom f f x = G Y

Proof

Step Hyp Ref Expression
1 bnj1514.1 B = d | d A x d pred x A R d
2 bnj1514.2 Y = x f pred x A R
3 bnj1514.3 C = f | d B f Fn d x d f x = G Y
4 3 bnj1436 f C d B f Fn d x d f x = G Y
5 df-rex d B f Fn d x d f x = G Y d d B f Fn d x d f x = G Y
6 3anass d B f Fn d x d f x = G Y d B f Fn d x d f x = G Y
7 5 6 bnj133 d B f Fn d x d f x = G Y d d B f Fn d x d f x = G Y
8 4 7 sylib f C d d B f Fn d x d f x = G Y
9 simp3 d B f Fn d x d f x = G Y x d f x = G Y
10 fndm f Fn d dom f = d
11 10 3ad2ant2 d B f Fn d x d f x = G Y dom f = d
12 11 raleqdv d B f Fn d x d f x = G Y x dom f f x = G Y x d f x = G Y
13 9 12 mpbird d B f Fn d x d f x = G Y x dom f f x = G Y
14 8 13 bnj593 f C d x dom f f x = G Y
15 14 bnj937 f C x dom f f x = G Y