src/HOL/Divides.thy
changeset 60516 0826b7025d07
parent 60429 d3d1e185cd63
child 60517 f16e4fb20652
equal deleted inserted replaced
60515:484559628038 60516:0826b7025d07
   128   then show ?thesis by (rule add_left_imp_eq)
   128   then show ?thesis by (rule add_left_imp_eq)
   129 qed
   129 qed
   130 
   130 
   131 lemma mod_self [simp]: "a mod a = 0"
   131 lemma mod_self [simp]: "a mod a = 0"
   132   using mod_mult_self2_is_0 [of 1] by simp
   132   using mod_mult_self2_is_0 [of 1] by simp
   133 
       
   134 lemma div_self [simp]: "a \<noteq> 0 \<Longrightarrow> a div a = 1"
       
   135   using div_mult_self2_is_id [of _ 1] by simp
       
   136 
   133 
   137 lemma div_add_self1 [simp]:
   134 lemma div_add_self1 [simp]:
   138   assumes "b \<noteq> 0"
   135   assumes "b \<noteq> 0"
   139   shows "(b + a) div b = a div b + 1"
   136   shows "(b + a) div b = a div b + 1"
   140   using assms div_mult_self1 [of b a 1] by (simp add: add.commute)
   137   using assms div_mult_self1 [of b a 1] by (simp add: add.commute)