English
The product of weighted homogeneous polynomials of degrees m and n is weighted homogeneous of degree m+n.
Русский
Произведение взвешенно однородных полиномов степеней m и n — взвешенно однородно степени m+n.
LaTeX
$$IsWeightedHomogeneous w φ m → IsWeightedHomogeneous w ψ n → IsWeightedHomogeneous w (φ*ψ) (m+n)$$
Lean4
/-- The product of weighted homogeneous polynomials of weighted degrees `m` and `n` is weighted
homogeneous of weighted degree `m + n`. -/
theorem mul {w : σ → M} (hφ : IsWeightedHomogeneous w φ m) (hψ : IsWeightedHomogeneous w ψ n) :
IsWeightedHomogeneous w (φ * ψ) (m + n) :=
weightedHomogeneousSubmodule_mul w m n <| Submodule.mul_mem_mul hφ hψ