Intuitionistic Logic Explorer |
< Previous
Next >
Nearby theorems |
||
Mirrors > Home > ILE Home > Th. List > 2p2e4 | GIF version |
Description: Two plus two equals four. For more information, see "2+2=4 Trivia" on the Metamath Proof Explorer Home Page: https://us.metamath.org/mpeuni/mmset.html#trivia. (Contributed by NM, 27-May-1999.) |
Ref | Expression |
---|---|
2p2e4 | ⊢ (2 + 2) = 4 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-2 8772 | . . 3 ⊢ 2 = (1 + 1) | |
2 | 1 | oveq2i 5778 | . 2 ⊢ (2 + 2) = (2 + (1 + 1)) |
3 | df-4 8774 | . . 3 ⊢ 4 = (3 + 1) | |
4 | df-3 8773 | . . . 4 ⊢ 3 = (2 + 1) | |
5 | 4 | oveq1i 5777 | . . 3 ⊢ (3 + 1) = ((2 + 1) + 1) |
6 | 2cn 8784 | . . . 4 ⊢ 2 ∈ ℂ | |
7 | ax-1cn 7706 | . . . 4 ⊢ 1 ∈ ℂ | |
8 | 6, 7, 7 | addassi 7767 | . . 3 ⊢ ((2 + 1) + 1) = (2 + (1 + 1)) |
9 | 3, 5, 8 | 3eqtri 2162 | . 2 ⊢ 4 = (2 + (1 + 1)) |
10 | 2, 9 | eqtr4i 2161 | 1 ⊢ (2 + 2) = 4 |
Colors of variables: wff set class |
Syntax hints: = wceq 1331 (class class class)co 5767 1c1 7614 + caddc 7616 2c2 8764 3c3 8765 4c4 8766 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 105 ax-ia2 106 ax-ia3 107 ax-io 698 ax-5 1423 ax-7 1424 ax-gen 1425 ax-ie1 1469 ax-ie2 1470 ax-8 1482 ax-10 1483 ax-11 1484 ax-i12 1485 ax-bndl 1486 ax-4 1487 ax-17 1506 ax-i9 1510 ax-ial 1514 ax-i5r 1515 ax-ext 2119 ax-resscn 7705 ax-1cn 7706 ax-1re 7707 ax-addrcl 7710 ax-addass 7715 |
This theorem depends on definitions: df-bi 116 df-3an 964 df-tru 1334 df-nf 1437 df-sb 1736 df-clab 2124 df-cleq 2130 df-clel 2133 df-nfc 2268 df-rex 2420 df-v 2683 df-un 3070 df-in 3072 df-ss 3079 df-sn 3528 df-pr 3529 df-op 3531 df-uni 3732 df-br 3925 df-iota 5083 df-fv 5126 df-ov 5770 df-2 8772 df-3 8773 df-4 8774 |
This theorem is referenced by: 2t2e4 8867 i4 10388 4bc2eq6 10513 resqrexlemover 10775 resqrexlemcalc1 10779 ef01bndlem 11452 6gcd4e2 11672 |
Copyright terms: Public domain | W3C validator |