diff --git a/Mathlib/Data/MvPolynomial/Variables.lean b/Mathlib/Data/MvPolynomial/Variables.lean index c8ce16d44cb0c..486df48dbb3d7 100644 --- a/Mathlib/Data/MvPolynomial/Variables.lean +++ b/Mathlib/Data/MvPolynomial/Variables.lean @@ -566,6 +566,18 @@ theorem degreeOf_mul_X_eq (j : σ) (f : MvPolynomial σ R) : set_option linter.uppercaseLean3 false in #align mv_polynomial.degree_of_mul_X_eq MvPolynomial.degreeOf_mul_X_eq +theorem degreeOf_C_mul_le (p : MvPolynomial σ R) (i : σ) (c : R) : + (C c * p).degreeOf i ≤ p.degreeOf i := by + unfold degreeOf + convert Multiset.count_le_of_le i <| degrees_mul (C c) p + simp [degrees_C] + +theorem degreeOf_mul_C_le (p : MvPolynomial σ R) (i : σ) (c : R) : + (p * C c).degreeOf i ≤ p.degreeOf i := by + unfold degreeOf + convert Multiset.count_le_of_le i <| degrees_mul p (C c) + simp [degrees_C] + theorem degreeOf_rename_of_injective {p : MvPolynomial σ R} {f : σ → τ} (h : Function.Injective f) (i : σ) : degreeOf (f i) (rename f p) = degreeOf i p := by classical