Description: Minus one plus one is zero for signed reals. (Contributed by NM, 5-May-1996) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Assertion | m1p1sr | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-m1r | |
|
2 | df-1r | |
|
3 | 1 2 | oveq12i | |
4 | df-0r | |
|
5 | 1pr | |
|
6 | addclpr | |
|
7 | 5 5 6 | mp2an | |
8 | addsrpr | |
|
9 | 5 7 7 5 8 | mp4an | |
10 | addasspr | |
|
11 | 10 | oveq2i | |
12 | addclpr | |
|
13 | 5 7 12 | mp2an | |
14 | addclpr | |
|
15 | 7 5 14 | mp2an | |
16 | enreceq | |
|
17 | 5 5 13 15 16 | mp4an | |
18 | 11 17 | mpbir | |
19 | 9 18 | eqtr4i | |
20 | 4 19 | eqtr4i | |
21 | 3 20 | eqtr4i | |