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Metamath Proof Explorer

Theorem neg1cn

Description: -1 is a complex number. (Contributed by David A. Wheeler, 7-Jul-2016)

Ref Expression
Assertion neg1cn 
|- -u 1 e. CC

Proof

Step Hyp Ref Expression
1 ax-1cn 
 |-  1 e. CC
2 1 negcli 
 |-  -u 1 e. CC