English
Instance giving a MulAction on the carrier of X in Action.FintypeCat, via the previous instance.
Русский
Инстанс MulAction на носитель X в Action.FintypeCat через предыдущий инстанс.
LaTeX
$$$\text{instMulActionCarrier}$$$
Lean4
instance instMulAction {G : Type*} [Monoid G] (X : Action V G) : MulAction G (ToType X)
where
smul g x := ConcreteCategory.hom (X.ρ g) x
one_smul
x := by
change ConcreteCategory.hom (X.ρ 1) x = x
simp
mul_smul g h
x :=
by
change ConcreteCategory.hom (X.ρ (g * h)) x = ConcreteCategory.hom (X.ρ g) ((ConcreteCategory.hom (X.ρ h)) x)
simp
/- Specialize `instMulAction` to assist typeclass inference. -/