∀ (R : Type uR) (S : Type uS) {ι : Type uι} (M₂ : Type v₂) (M₃ : Type v₃) [inst : Semiring R]
  [inst_1 : AddCommMonoid M₂] [inst_2 : Module R M₂] [inst_3 : Semiring S] [inst_4 : AddCommMonoid M₃]
  [inst_5 : Module S M₃] [inst_6 : Module R M₃] [inst_7 : SMulCommClass R S M₃] [inst_8 : Subsingleton ι] (i : ι)
  (a : MultilinearMap R (fun x => M₂) M₃),
  (MultilinearMap.ofSubsingletonₗ R S M₂ M₃ i).symm a = (MultilinearMap.ofSubsingleton R M₂ M₃ i).symm a