Metamath Proof Explorer


Theorem subresre

Description: Subtraction restricted to the reals. (Contributed by SN, 5-May-2024)

Ref Expression
Assertion subresre
|- -R = ( - |` ( RR X. RR ) )

Proof

Step Hyp Ref Expression
1 resubeqsub
 |-  ( ( x e. RR /\ y e. RR ) -> ( x -R y ) = ( x - y ) )
2 1 3adant1
 |-  ( ( T. /\ x e. RR /\ y e. RR ) -> ( x -R y ) = ( x - y ) )
3 ax-resscn
 |-  RR C_ CC
4 3 a1i
 |-  ( T. -> RR C_ CC )
5 resubf
 |-  -R : ( RR X. RR ) --> RR
6 5 a1i
 |-  ( T. -> -R : ( RR X. RR ) --> RR )
7 sn-subf
 |-  - : ( CC X. CC ) --> CC
8 7 a1i
 |-  ( T. -> - : ( CC X. CC ) --> CC )
9 2 4 6 8 oprres
 |-  ( T. -> -R = ( - |` ( RR X. RR ) ) )
10 9 mptru
 |-  -R = ( - |` ( RR X. RR ) )