Metamath Proof Explorer


Theorem wl-nfae1

Description: Unlike nfae , this specialized theorem avoids ax-11 . (Contributed by Wolf Lammen, 26-Jun-2019)

Ref Expression
Assertion wl-nfae1 xyy=x

Proof

Step Hyp Ref Expression
1 aecom yy=xxx=y
2 nfa1 xxx=y
3 1 2 nfxfr xyy=x