Metamath Proof Explorer


Theorem cjred

Description: A real number equals its complex conjugate. Proposition 10-3.4(f) of Gleason p. 133. (Contributed by Mario Carneiro, 29-May-2016)

Ref Expression
Hypothesis crred.1 φ A
Assertion cjred φ A = A

Proof

Step Hyp Ref Expression
1 crred.1 φ A
2 cjre A A = A
3 1 2 syl φ A = A