English
If A has NoZeroSMulDivisors and R acts faithfully on A, then NoZeroSMulDivisors R A holds.
Русский
Если A не имеет нулевых делителей под действием и R действует достоверно на A, то NoZeroSMulDivisors R A верно.
LaTeX
$$$\mathrm{NoZeroSMulDivisors}\; R\; A.$$$
Lean4
instance (priority := 100) instOfFaithfulSMul {R A : Type*} [CommSemiring R] [Semiring A] [Algebra R A]
[NoZeroDivisors A] [FaithfulSMul R A] : NoZeroSMulDivisors R A :=
⟨fun hcx =>
(mul_eq_zero.mp ((Algebra.smul_def _ _).symm.trans hcx)).imp_left
(map_eq_zero_iff (algebraMap R A) <| FaithfulSMul.algebraMap_injective R A).mp⟩