Metamath Proof Explorer


Theorem cgrtr

Description: Transitivity law for congruence. Theorem 2.3 of Schwabhauser p. 27. (Contributed by Scott Fenton, 24-Sep-2013)

Ref Expression
Assertion cgrtr N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N A B Cgr C D C D Cgr E F A B Cgr E F

Proof

Step Hyp Ref Expression
1 simp1 N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N N
2 simp23 N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N C 𝔼 N
3 simp31 N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N D 𝔼 N
4 simp21 N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N A 𝔼 N
5 simp22 N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N B 𝔼 N
6 simp32 N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N E 𝔼 N
7 simp33 N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N F 𝔼 N
8 simprl N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N A B Cgr C D C D Cgr E F A B Cgr C D
9 1 4 5 2 3 8 cgrcomand N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N A B Cgr C D C D Cgr E F C D Cgr A B
10 simprr N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N A B Cgr C D C D Cgr E F C D Cgr E F
11 1 2 3 4 5 6 7 9 10 cgrtr4and N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N A B Cgr C D C D Cgr E F A B Cgr E F
12 11 ex N A 𝔼 N B 𝔼 N C 𝔼 N D 𝔼 N E 𝔼 N F 𝔼 N A B Cgr C D C D Cgr E F A B Cgr E F