Theorem: exercise3_7 (LeanCourse/Assignments/Assignment3.lean)

State before:
α : Type u_1
β : Type u_2
f : α → β
s : Set α
t : Set β
⊢ f '' s ∩ t = f '' (s ∩ f ⁻¹' t)
Tactic:
sorry
State after:
no goals