Metamath Proof Explorer


Theorem m1p1sr

Description: Minus one plus one is zero for signed reals. (Contributed by NM, 5-May-1996) (New usage is discouraged.)

Ref Expression
Assertion m1p1sr -1 𝑹 + 𝑹 1 𝑹 = 0 𝑹

Proof

Step Hyp Ref Expression
1 df-m1r -1 𝑹 = 1 𝑷 1 𝑷 + 𝑷 1 𝑷 ~ 𝑹
2 df-1r 1 𝑹 = 1 𝑷 + 𝑷 1 𝑷 1 𝑷 ~ 𝑹
3 1 2 oveq12i -1 𝑹 + 𝑹 1 𝑹 = 1 𝑷 1 𝑷 + 𝑷 1 𝑷 ~ 𝑹 + 𝑹 1 𝑷 + 𝑷 1 𝑷 1 𝑷 ~ 𝑹
4 df-0r 0 𝑹 = 1 𝑷 1 𝑷 ~ 𝑹
5 1pr 1 𝑷 𝑷
6 addclpr 1 𝑷 𝑷 1 𝑷 𝑷 1 𝑷 + 𝑷 1 𝑷 𝑷
7 5 5 6 mp2an 1 𝑷 + 𝑷 1 𝑷 𝑷
8 addsrpr 1 𝑷 𝑷 1 𝑷 + 𝑷 1 𝑷 𝑷 1 𝑷 + 𝑷 1 𝑷 𝑷 1 𝑷 𝑷 1 𝑷 1 𝑷 + 𝑷 1 𝑷 ~ 𝑹 + 𝑹 1 𝑷 + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 = 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 ~ 𝑹
9 5 7 7 5 8 mp4an 1 𝑷 1 𝑷 + 𝑷 1 𝑷 ~ 𝑹 + 𝑹 1 𝑷 + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 = 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 ~ 𝑹
10 addasspr 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 = 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷
11 10 oveq2i 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 = 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷
12 addclpr 1 𝑷 𝑷 1 𝑷 + 𝑷 1 𝑷 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 𝑷
13 5 7 12 mp2an 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 𝑷
14 addclpr 1 𝑷 + 𝑷 1 𝑷 𝑷 1 𝑷 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 𝑷
15 7 5 14 mp2an 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 𝑷
16 enreceq 1 𝑷 𝑷 1 𝑷 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 𝑷 1 𝑷 1 𝑷 ~ 𝑹 = 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 ~ 𝑹 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 = 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷
17 5 5 13 15 16 mp4an 1 𝑷 1 𝑷 ~ 𝑹 = 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 ~ 𝑹 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 = 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷
18 11 17 mpbir 1 𝑷 1 𝑷 ~ 𝑹 = 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 ~ 𝑹
19 9 18 eqtr4i 1 𝑷 1 𝑷 + 𝑷 1 𝑷 ~ 𝑹 + 𝑹 1 𝑷 + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 = 1 𝑷 1 𝑷 ~ 𝑹
20 4 19 eqtr4i 0 𝑹 = 1 𝑷 1 𝑷 + 𝑷 1 𝑷 ~ 𝑹 + 𝑹 1 𝑷 + 𝑷 1 𝑷 1 𝑷 ~ 𝑹
21 3 20 eqtr4i -1 𝑹 + 𝑹 1 𝑹 = 0 𝑹