Theorem 1bi 119

Description: Identity inference. (Contributed by NM, 30-Aug-1997.)

Hypothesis

Ref	Expression
1bi.1	a = b

Assertion

Ref	Expression
1bi	1 = (a ≡ b)

Proof of Theorem 1bi

Step	Hyp	Ref	Expression
1		1bi.1	. . 3 a = b
2	1	bi1 118	. 2 (a ≡ b) = 1
3	2	ax-r1 35	1 1 = (a ≡ b)

Syntax hints:   = wb 1   ≡ tb 5  1wt 8

This theorem was proved from axioms:  ax-a1 30  ax-a2 31  ax-a5 34  ax-r1 35  ax-r2 36  ax-r4 37  ax-r5 38

This theorem depends on definitions:  df-b 39  df-a 40  df-t 41  df-f 42

This theorem is referenced by:  wed  441  oi3oa3  733