src/HOL/Library/Fundamental_Theorem_Algebra.thy
changeset 62128 3201ddb00097
parent 61945 1135b8de26c3
child 63060 293ede07b775
equal deleted inserted replaced
62127:d8e7738bd2e9 62128:3201ddb00097
  1064     then show ?thesis
  1064     then show ?thesis
  1065       unfolding constant_def by auto
  1065       unfolding constant_def by auto
  1066   qed
  1066   qed
  1067 qed
  1067 qed
  1068 
  1068 
  1069 lemma divides_degree:
       
  1070   assumes pq: "p dvd (q:: complex poly)"
       
  1071   shows "degree p \<le> degree q \<or> q = 0"
       
  1072   by (metis dvd_imp_degree_le pq)
       
  1073 
       
  1074 text \<open>Arithmetic operations on multivariate polynomials.\<close>
  1069 text \<open>Arithmetic operations on multivariate polynomials.\<close>
  1075 
  1070 
  1076 lemma mpoly_base_conv:
  1071 lemma mpoly_base_conv:
  1077   fixes x :: "'a::comm_ring_1"
  1072   fixes x :: "'a::comm_ring_1"
  1078   shows "0 = poly 0 x" "c = poly [:c:] x" "x = poly [:0,1:] x"
  1073   shows "0 = poly 0 x" "c = poly [:c:] x" "x = poly [:0,1:] x"