Metamath Proof Explorer


Theorem midofsegid

Description: If two points fall in the same place in the middle of a segment, then they are identical. (Contributed by Scott Fenton, 16-Oct-2013) (Revised by Mario Carneiro, 19-Apr-2014)

Ref Expression
Assertion midofsegid ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) → ( ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) → 𝐷 = 𝐸 ) )

Proof

Step Hyp Ref Expression
1 simp1 ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) → 𝑁 ∈ ℕ )
2 simp2l ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) → 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) )
3 simp3r ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) → 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) )
4 simp3l ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) → 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) )
5 simprr ( ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) ∧ ( ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) ∧ 𝐷 Btwn ⟨ 𝐴 , 𝐸 ⟩ ) ) → 𝐷 Btwn ⟨ 𝐴 , 𝐸 ⟩ )
6 simprl3 ( ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) ∧ ( ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) ∧ 𝐷 Btwn ⟨ 𝐴 , 𝐸 ⟩ ) ) → ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ )
7 1 2 4 2 3 6 cgrcomand ( ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) ∧ ( ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) ∧ 𝐷 Btwn ⟨ 𝐴 , 𝐸 ⟩ ) ) → ⟨ 𝐴 , 𝐸 ⟩ Cgr ⟨ 𝐴 , 𝐷 ⟩ )
8 1 2 3 4 5 7 endofsegidand ( ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) ∧ ( ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) ∧ 𝐷 Btwn ⟨ 𝐴 , 𝐸 ⟩ ) ) → 𝐸 = 𝐷 )
9 8 eqcomd ( ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) ∧ ( ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) ∧ 𝐷 Btwn ⟨ 𝐴 , 𝐸 ⟩ ) ) → 𝐷 = 𝐸 )
10 9 expr ( ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) ∧ ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) ) → ( 𝐷 Btwn ⟨ 𝐴 , 𝐸 ⟩ → 𝐷 = 𝐸 ) )
11 simprr ( ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) ∧ ( ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐷 ⟩ ) ) → 𝐸 Btwn ⟨ 𝐴 , 𝐷 ⟩ )
12 simprl3 ( ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) ∧ ( ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐷 ⟩ ) ) → ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ )
13 1 2 4 3 11 12 endofsegidand ( ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) ∧ ( ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐷 ⟩ ) ) → 𝐷 = 𝐸 )
14 13 expr ( ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) ∧ ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) ) → ( 𝐸 Btwn ⟨ 𝐴 , 𝐷 ⟩ → 𝐷 = 𝐸 ) )
15 3simpa ( ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) → ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ) )
16 15 adantl ( ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) ∧ ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) ) → ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ) )
17 simp2r ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) → 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) )
18 btwnconn3 ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ) → ( ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ) → ( 𝐷 Btwn ⟨ 𝐴 , 𝐸 ⟩ ∨ 𝐸 Btwn ⟨ 𝐴 , 𝐷 ⟩ ) ) )
19 1 2 4 3 17 18 syl122anc ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) → ( ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ) → ( 𝐷 Btwn ⟨ 𝐴 , 𝐸 ⟩ ∨ 𝐸 Btwn ⟨ 𝐴 , 𝐷 ⟩ ) ) )
20 19 adantr ( ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) ∧ ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) ) → ( ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ) → ( 𝐷 Btwn ⟨ 𝐴 , 𝐸 ⟩ ∨ 𝐸 Btwn ⟨ 𝐴 , 𝐷 ⟩ ) ) )
21 16 20 mpd ( ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) ∧ ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) ) → ( 𝐷 Btwn ⟨ 𝐴 , 𝐸 ⟩ ∨ 𝐸 Btwn ⟨ 𝐴 , 𝐷 ⟩ ) )
22 10 14 21 mpjaod ( ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) ∧ ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) ) → 𝐷 = 𝐸 )
23 22 ex ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) ∧ ( 𝐷 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐸 ∈ ( 𝔼 ‘ 𝑁 ) ) ) → ( ( 𝐷 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ 𝐸 Btwn ⟨ 𝐴 , 𝐵 ⟩ ∧ ⟨ 𝐴 , 𝐷 ⟩ Cgr ⟨ 𝐴 , 𝐸 ⟩ ) → 𝐷 = 𝐸 ) )