Metamath Proof Explorer


Theorem cjmulrcli

Description: A complex number times its conjugate is real. (Contributed by NM, 11-May-1999)

Ref Expression
Hypothesis recl.1 A
Assertion cjmulrcli A A

Proof

Step Hyp Ref Expression
1 recl.1 A
2 cjmulrcl A A A
3 1 2 ax-mp A A