Metamath Proof Explorer


Theorem 2timesi

Description: Two times a number. (Contributed by NM, 1-Aug-1999)

Ref Expression
Hypothesis 2timesi.1
|- A e. CC
Assertion 2timesi
|- ( 2 x. A ) = ( A + A )

Proof

Step Hyp Ref Expression
1 2timesi.1
 |-  A e. CC
2 2times
 |-  ( A e. CC -> ( 2 x. A ) = ( A + A ) )
3 1 2 ax-mp
 |-  ( 2 x. A ) = ( A + A )