Theorem: Graph.PathClass.append_mul (Lectures/Graph.lean)

State before:
V : Type u
E : Type v
G : Graph V E
u✝ v✝ w✝ : V
e : EdgeBetween G v✝ w✝
v w u : V
p : EdgePath G v w
q : EdgePath G w u
⊢ [[p ++ q]] = mul [[p]] [[q]]
Tactic:
rfl
State after:
no goals