∀ (R : Type u_1) [inst : CommSemiring R] (M : Type u_2) (N : Type u_3) [inst_1 : AddCommMonoid M]
  [inst_2 : AddCommMonoid N] [inst_3 : Module R M] [inst_4 : Module R N] (f : R →ₗ[R] N),
  Function.Injective ⇑f → ∀ [Module.Flat R M] [Nontrivial M], Nontrivial (TensorProduct R M N)