Metamath Proof Explorer


Theorem chm1i

Description: Meet with lattice one in CH . (Contributed by NM, 24-Oct-1999) (New usage is discouraged.)

Ref Expression
Hypothesis ch0le.1 A C
Assertion chm1i A = A

Proof

Step Hyp Ref Expression
1 ch0le.1 A C
2 1 chssii A
3 df-ss A A = A
4 2 3 mpbi A = A