Metamath Proof Explorer


Theorem efgmf

Description: The formal inverse operation is an endofunction on the generating set. (Contributed by Mario Carneiro, 27-Sep-2015)

Ref Expression
Hypothesis efgmval.m M = y I , z 2 𝑜 y 1 𝑜 z
Assertion efgmf M : I × 2 𝑜 I × 2 𝑜

Proof

Step Hyp Ref Expression
1 efgmval.m M = y I , z 2 𝑜 y 1 𝑜 z
2 2oconcl z 2 𝑜 1 𝑜 z 2 𝑜
3 opelxpi y I 1 𝑜 z 2 𝑜 y 1 𝑜 z I × 2 𝑜
4 2 3 sylan2 y I z 2 𝑜 y 1 𝑜 z I × 2 𝑜
5 4 rgen2 y I z 2 𝑜 y 1 𝑜 z I × 2 𝑜
6 1 fmpo y I z 2 𝑜 y 1 𝑜 z I × 2 𝑜 M : I × 2 𝑜 I × 2 𝑜
7 5 6 mpbi M : I × 2 𝑜 I × 2 𝑜