src/HOL/Limits.thy
changeset 70803 2d658afa1fc0
parent 70723 4e39d87c9737
child 70804 4eef7c6ef7bf
equal deleted inserted replaced
70802:160eaf566bcb 70803:2d658afa1fc0
   777 
   777 
   778 lemma tendsto_mult_right: "(f \<longlongrightarrow> l) F \<Longrightarrow> ((\<lambda>x. (f x) * c) \<longlongrightarrow> l * c) F"
   778 lemma tendsto_mult_right: "(f \<longlongrightarrow> l) F \<Longrightarrow> ((\<lambda>x. (f x) * c) \<longlongrightarrow> l * c) F"
   779   for c :: "'a::topological_semigroup_mult"
   779   for c :: "'a::topological_semigroup_mult"
   780   by (rule tendsto_mult [OF _ tendsto_const])
   780   by (rule tendsto_mult [OF _ tendsto_const])
   781 
   781 
   782 lemma real_tendsto_mult_left_iff:
   782 lemma tendsto_mult_left_iff:
   783    "c \<noteq> 0 \<Longrightarrow> tendsto(\<lambda>x. c * f x) (c * l) F \<longleftrightarrow> tendsto f l F" for c :: real
   783    "c \<noteq> 0 \<Longrightarrow> tendsto(\<lambda>x. c * f x) (c * l) F \<longleftrightarrow> tendsto f l F" for c :: "'a::{topological_semigroup_mult,field}"
   784   by (auto simp: tendsto_mult_left dest: tendsto_mult_left [where c = "1/c"])
   784   by (auto simp: tendsto_mult_left dest: tendsto_mult_left [where c = "1/c"])
   785 
   785 
   786 lemma real_tendsto_mult_right_iff:
   786 lemma tendsto_mult_right_iff:
   787    "c \<noteq> 0 \<Longrightarrow> tendsto(\<lambda>x. f x * c) (l * c) F \<longleftrightarrow> tendsto f l F" for c :: real
   787    "c \<noteq> 0 \<Longrightarrow> tendsto(\<lambda>x. f x * c) (l * c) F \<longleftrightarrow> tendsto f l F" for c :: "'a::{topological_semigroup_mult,field}"
   788   by (simp add: mult.commute real_tendsto_mult_left_iff)
   788   by (auto simp: tendsto_mult_right dest: tendsto_mult_left [where c = "1/c"])
   789 
   789 
   790 lemma lim_const_over_n [tendsto_intros]:
   790 lemma lim_const_over_n [tendsto_intros]:
   791   fixes a :: "'a::real_normed_field"
   791   fixes a :: "'a::real_normed_field"
   792   shows "(\<lambda>n. a / of_nat n) \<longlonglongrightarrow> 0"
   792   shows "(\<lambda>n. a / of_nat n) \<longlonglongrightarrow> 0"
   793   using tendsto_mult [OF tendsto_const [of a] lim_1_over_n] by simp
   793   using tendsto_mult [OF tendsto_const [of a] lim_1_over_n] by simp