Metamath Proof Explorer


Theorem s7eqd

Description: Equality theorem for a length 7 word. (Contributed by Mario Carneiro, 27-Feb-2016)

Ref Expression
Hypotheses s2eqd.1
|- ( ph -> A = N )
s2eqd.2
|- ( ph -> B = O )
s3eqd.3
|- ( ph -> C = P )
s4eqd.4
|- ( ph -> D = Q )
s5eqd.5
|- ( ph -> E = R )
s6eqd.6
|- ( ph -> F = S )
s7eqd.6
|- ( ph -> G = T )
Assertion s7eqd
|- ( ph -> <" A B C D E F G "> = <" N O P Q R S T "> )

Proof

Step Hyp Ref Expression
1 s2eqd.1
 |-  ( ph -> A = N )
2 s2eqd.2
 |-  ( ph -> B = O )
3 s3eqd.3
 |-  ( ph -> C = P )
4 s4eqd.4
 |-  ( ph -> D = Q )
5 s5eqd.5
 |-  ( ph -> E = R )
6 s6eqd.6
 |-  ( ph -> F = S )
7 s7eqd.6
 |-  ( ph -> G = T )
8 1 2 3 4 5 6 s6eqd
 |-  ( ph -> <" A B C D E F "> = <" N O P Q R S "> )
9 7 s1eqd
 |-  ( ph -> <" G "> = <" T "> )
10 8 9 oveq12d
 |-  ( ph -> ( <" A B C D E F "> ++ <" G "> ) = ( <" N O P Q R S "> ++ <" T "> ) )
11 df-s7
 |-  <" A B C D E F G "> = ( <" A B C D E F "> ++ <" G "> )
12 df-s7
 |-  <" N O P Q R S T "> = ( <" N O P Q R S "> ++ <" T "> )
13 10 11 12 3eqtr4g
 |-  ( ph -> <" A B C D E F G "> = <" N O P Q R S T "> )