Theorem: derivative_emptySet (Katydid/Conal/Calculus.lean)

State before:
α : Type u_1
⊢ (a : α) → δ' ∅ a ≡ ∅
Tactic:
intro a
State after:
α : Type u_1
a : α
⊢ δ' ∅ a ≡ ∅

State before:
α : Type u_1
a : α
⊢ δ' ∅ a ≡ ∅
Tactic:
constructor
State after:
case a
α : Type u_1
a : α
⊢ δ' ∅ a = ∅

State before:
case a
α : Type u_1
a : α
⊢ δ' ∅ a = ∅
Tactic:
rfl
State after:
no goals