Metamath Proof Explorer


Theorem gsumccatsn

Description: Homomorphic property of composites with a singleton. (Contributed by AV, 20-Jan-2019)

Ref Expression
Hypotheses gsumccat.b B = Base G
gsumccat.p + ˙ = + G
Assertion gsumccatsn G Mnd W Word B Z B G W ++ ⟨“ Z ”⟩ = G W + ˙ Z

Proof

Step Hyp Ref Expression
1 gsumccat.b B = Base G
2 gsumccat.p + ˙ = + G
3 s1cl Z B ⟨“ Z ”⟩ Word B
4 1 2 gsumccat G Mnd W Word B ⟨“ Z ”⟩ Word B G W ++ ⟨“ Z ”⟩ = G W + ˙ G ⟨“ Z ”⟩
5 3 4 syl3an3 G Mnd W Word B Z B G W ++ ⟨“ Z ”⟩ = G W + ˙ G ⟨“ Z ”⟩
6 1 gsumws1 Z B G ⟨“ Z ”⟩ = Z
7 6 3ad2ant3 G Mnd W Word B Z B G ⟨“ Z ”⟩ = Z
8 7 oveq2d G Mnd W Word B Z B G W + ˙ G ⟨“ Z ”⟩ = G W + ˙ Z
9 5 8 eqtrd G Mnd W Word B Z B G W ++ ⟨“ Z ”⟩ = G W + ˙ Z