Metamath Proof Explorer


Theorem eengstr

Description: The Euclidean geometry as a structure. (Contributed by Thierry Arnoux, 15-Mar-2019)

Ref Expression
Assertion eengstr N 𝔼 𝒢 N Struct 1 17

Proof

Step Hyp Ref Expression
1 eengv N 𝔼 𝒢 N = Base ndx 𝔼 N dist ndx x 𝔼 N , y 𝔼 N i = 1 N x i y i 2 Itv ndx x 𝔼 N , y 𝔼 N z 𝔼 N | z Btwn x y Line 𝒢 ndx x 𝔼 N , y 𝔼 N x z 𝔼 N | z Btwn x y x Btwn z y y Btwn x z
2 1nn 1
3 basendx Base ndx = 1
4 2nn0 2 0
5 1nn0 1 0
6 1lt10 1 < 10
7 2 4 5 6 declti 1 < 12
8 2nn 2
9 5 8 decnncl 12
10 dsndx dist ndx = 12
11 2 3 7 9 10 strle2 Base ndx 𝔼 N dist ndx x 𝔼 N , y 𝔼 N i = 1 N x i y i 2 Struct 1 12
12 6nn 6
13 5 12 decnncl 16
14 itvndx Itv ndx = 16
15 6nn0 6 0
16 7nn 7
17 6lt7 6 < 7
18 5 15 16 17 declt 16 < 17
19 5 16 decnncl 17
20 lngndx Line 𝒢 ndx = 17
21 13 14 18 19 20 strle2 Itv ndx x 𝔼 N , y 𝔼 N z 𝔼 N | z Btwn x y Line 𝒢 ndx x 𝔼 N , y 𝔼 N x z 𝔼 N | z Btwn x y x Btwn z y y Btwn x z Struct 16 17
22 2lt6 2 < 6
23 5 4 12 22 declt 12 < 16
24 11 21 23 strleun Base ndx 𝔼 N dist ndx x 𝔼 N , y 𝔼 N i = 1 N x i y i 2 Itv ndx x 𝔼 N , y 𝔼 N z 𝔼 N | z Btwn x y Line 𝒢 ndx x 𝔼 N , y 𝔼 N x z 𝔼 N | z Btwn x y x Btwn z y y Btwn x z Struct 1 17
25 1 24 eqbrtrdi N 𝔼 𝒢 N Struct 1 17