Description: Subtraction restricted to the reals. (Contributed by SN, 5-May-2024)
Ref | Expression | ||
---|---|---|---|
Assertion | subresre | |- -R = ( - |` ( RR X. RR ) ) |
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 ) ) |