Metamath Proof Explorer


Theorem resubid1

Description: Real number version of subid1 , without ax-mulcom . (Contributed by SN, 23-Jan-2024)

Ref Expression
Assertion resubid1
|- ( A e. RR -> ( A -R 0 ) = A )

Proof

Step Hyp Ref Expression
1 readdid2
 |-  ( A e. RR -> ( 0 + A ) = A )
2 id
 |-  ( A e. RR -> A e. RR )
3 elre0re
 |-  ( A e. RR -> 0 e. RR )
4 2 3 2 resubaddd
 |-  ( A e. RR -> ( ( A -R 0 ) = A <-> ( 0 + A ) = A ) )
5 1 4 mpbird
 |-  ( A e. RR -> ( A -R 0 ) = A )