English
Let x be integral over R in a nontrivial S-algebra; then the degree of the divisor-minpoly of x over R is strictly smaller than the degree of the minimal polynomial of x over R.
Русский
Пусть x элемент, целочисленный над R в негодной S-алгебре; тогда deg(minpolyDiv R x) строго меньше deg(minpoly R x).
LaTeX
$$$\operatorname{natDegree}(\minpoly\_D R\ x) < \operatorname{natDegree}(\minpoly\ R\ x)$$$
Lean4
theorem natDegree_minpolyDiv_lt [Nontrivial S] : natDegree (minpolyDiv R x) < natDegree (minpoly R x) :=
by
rw [← natDegree_minpolyDiv_succ hx]
exact Nat.lt_succ_self _