equal
deleted
inserted
replaced
310 show "eventually (\<lambda>x. (f x, g x) \<in> S) net" |
310 show "eventually (\<lambda>x. (f x, g x) \<in> S) net" |
311 by (rule eventually_elim2) |
311 by (rule eventually_elim2) |
312 (simp add: subsetD [OF `A \<times> B \<subseteq> S`]) |
312 (simp add: subsetD [OF `A \<times> B \<subseteq> S`]) |
313 qed |
313 qed |
314 |
314 |
315 lemma LIM_fst: "f -- x --> a \<Longrightarrow> (\<lambda>x. fst (f x)) -- x --> fst a" |
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316 unfolding LIM_conv_tendsto by (rule tendsto_fst) |
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317 |
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318 lemma LIM_snd: "f -- x --> a \<Longrightarrow> (\<lambda>x. snd (f x)) -- x --> snd a" |
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319 unfolding LIM_conv_tendsto by (rule tendsto_snd) |
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320 |
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321 lemma LIM_Pair: |
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322 assumes "f -- x --> a" and "g -- x --> b" |
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323 shows "(\<lambda>x. (f x, g x)) -- x --> (a, b)" |
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324 using assms unfolding LIM_conv_tendsto |
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325 by (rule tendsto_Pair) |
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326 |
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327 lemma Cauchy_fst: "Cauchy X \<Longrightarrow> Cauchy (\<lambda>n. fst (X n))" |
315 lemma Cauchy_fst: "Cauchy X \<Longrightarrow> Cauchy (\<lambda>n. fst (X n))" |
328 unfolding Cauchy_def by (fast elim: le_less_trans [OF dist_fst_le]) |
316 unfolding Cauchy_def by (fast elim: le_less_trans [OF dist_fst_le]) |
329 |
317 |
330 lemma Cauchy_snd: "Cauchy X \<Longrightarrow> Cauchy (\<lambda>n. snd (X n))" |
318 lemma Cauchy_snd: "Cauchy X \<Longrightarrow> Cauchy (\<lambda>n. snd (X n))" |
331 unfolding Cauchy_def by (fast elim: le_less_trans [OF dist_snd_le]) |
319 unfolding Cauchy_def by (fast elim: le_less_trans [OF dist_snd_le]) |
346 then show "\<exists>n0. \<forall>m\<ge>n0. \<forall>n\<ge>n0. dist (X m, Y m) (X n, Y n) < r" .. |
334 then show "\<exists>n0. \<forall>m\<ge>n0. \<forall>n\<ge>n0. dist (X m, Y m) (X n, Y n) < r" .. |
347 qed |
335 qed |
348 |
336 |
349 lemma isCont_Pair [simp]: |
337 lemma isCont_Pair [simp]: |
350 "\<lbrakk>isCont f x; isCont g x\<rbrakk> \<Longrightarrow> isCont (\<lambda>x. (f x, g x)) x" |
338 "\<lbrakk>isCont f x; isCont g x\<rbrakk> \<Longrightarrow> isCont (\<lambda>x. (f x, g x)) x" |
351 unfolding isCont_def by (rule LIM_Pair) |
339 unfolding isCont_def by (rule tendsto_Pair) |
352 |
340 |
353 subsection {* Product is a complete metric space *} |
341 subsection {* Product is a complete metric space *} |
354 |
342 |
355 instance "*" :: (complete_space, complete_space) complete_space |
343 instance "*" :: (complete_space, complete_space) complete_space |
356 proof |
344 proof |