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 LIMSEQ_fst: "(X ----> a) \<Longrightarrow> (\<lambda>n. fst (X n)) ----> fst a" |
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316 unfolding LIMSEQ_conv_tendsto by (rule tendsto_fst) |
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317 |
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318 lemma LIMSEQ_snd: "(X ----> a) \<Longrightarrow> (\<lambda>n. snd (X n)) ----> snd a" |
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319 unfolding LIMSEQ_conv_tendsto by (rule tendsto_snd) |
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320 |
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321 lemma LIMSEQ_Pair: |
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322 assumes "X ----> a" and "Y ----> b" |
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323 shows "(\<lambda>n. (X n, Y n)) ----> (a, b)" |
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324 using assms unfolding LIMSEQ_conv_tendsto |
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325 by (rule tendsto_Pair) |
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326 |
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327 lemma LIM_fst: "f -- x --> a \<Longrightarrow> (\<lambda>x. fst (f x)) -- x --> fst a" |
315 lemma LIM_fst: "f -- x --> a \<Longrightarrow> (\<lambda>x. fst (f x)) -- x --> fst a" |
328 unfolding LIM_conv_tendsto by (rule tendsto_fst) |
316 unfolding LIM_conv_tendsto by (rule tendsto_fst) |
329 |
317 |
330 lemma LIM_snd: "f -- x --> a \<Longrightarrow> (\<lambda>x. snd (f x)) -- x --> snd a" |
318 lemma LIM_snd: "f -- x --> a \<Longrightarrow> (\<lambda>x. snd (f x)) -- x --> snd a" |
331 unfolding LIM_conv_tendsto by (rule tendsto_snd) |
319 unfolding LIM_conv_tendsto by (rule tendsto_snd) |
372 by (simp add: Cauchy_convergent_iff convergent_LIMSEQ_iff) |
360 by (simp add: Cauchy_convergent_iff convergent_LIMSEQ_iff) |
373 have 2: "(\<lambda>n. snd (X n)) ----> lim (\<lambda>n. snd (X n))" |
361 have 2: "(\<lambda>n. snd (X n)) ----> lim (\<lambda>n. snd (X n))" |
374 using Cauchy_snd [OF `Cauchy X`] |
362 using Cauchy_snd [OF `Cauchy X`] |
375 by (simp add: Cauchy_convergent_iff convergent_LIMSEQ_iff) |
363 by (simp add: Cauchy_convergent_iff convergent_LIMSEQ_iff) |
376 have "X ----> (lim (\<lambda>n. fst (X n)), lim (\<lambda>n. snd (X n)))" |
364 have "X ----> (lim (\<lambda>n. fst (X n)), lim (\<lambda>n. snd (X n)))" |
377 using LIMSEQ_Pair [OF 1 2] by simp |
365 using tendsto_Pair [OF 1 2] by simp |
378 then show "convergent X" |
366 then show "convergent X" |
379 by (rule convergentI) |
367 by (rule convergentI) |
380 qed |
368 qed |
381 |
369 |
382 subsection {* Product is a normed vector space *} |
370 subsection {* Product is a normed vector space *} |