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数学 高校生

なぜan≠0を確認するのですか?0だと成り立たないのはわかりますが、なぜ初めにそれを確認しようという考えになるんですか?

考え方 Check 例題292 分数型の漸化式 ( 1 ) a=- Focus で定義される数列{an}の一般項an を求めよ. EUDO MALWARE 1 an+1= 2 9 ○ an の逆数 フェン [an] (s) + Dg=+D THR An 2-an これまでに学んだ漸化式の解法が利用できないか考える。ここ では,漸化式の両辺の逆数をとって考える. ここで,(bm- 1 - をbn とおくと, 与えられた漸化式は,例題285 +29 an (p.505) のタイプ (an+1= pan+g) となる よって, 解 an+1=0 と仮定すると, これをくり返すと, an-1=An-2=・・・・・・=α1=0 1 となり, α= -≠0 と矛盾するので, an 0 (n≥1) 与えられた漸化式の両辺の逆数をとると, 1 2-an 2 an+1 an an 1 an = an= 3 漸化式と数学的帰納法 *** an=0 1 2-1+1 --1 n=1のとき, α= ASTERKE (南山大) ituto Ce *********** とおくと, bn+1−1=2(6n-1),bx-1=1 したがって,数列{bm-1} は初項1,公比2の等比数列だから、 bn-1=1・2n-1 より, bn=27-1+1 SCD &+s+an+ an+1= &+as+ bn+1=26-1,b1=-=2 a1 となり,n=k+1 のときも成り立つ. よって、すべてのに対して, an≠ 0 が成り立つ. 421 5 (1 -$+187 HEJN の逆数 2-an より, an=0 のとき, αk=0 と仮定すると,n=k+1 のとき,k+1=- an :=0 α=2α-1 より, a=1 1=27-1+1 より, an= 分数型の漸化式は逆数で考える 10.3 例題292 で an≠0 は,これから学ぶ数学的帰納法 (p.532〜) を用いた証明もでき 104030 る. <an=0 の数学的帰納法による証明> 1/12/3=1 -≠0 トキノを確認するときとの ちがいは? (- 1 2-1+1 HOHES - C ak 2-ak *0 513 + CES また、分数型の漸化式は,例題292のように逆数を考える方法だけでなく,例題 293 (p.516) のように特性方程式を利用する解き方もある。 SET 8 数 列

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英語 高校生

この文の第二段落のamid calls for ~のcallsは、名詞でしょうか?前置詞のamidとcalls forのつながりが、なぜこのような訳になるのか理解できません。このcalls が名詞だと仮定して直訳すると、管理下において大規模に火を放つことを求める要求の最中に... 続きを読む

王 jon 【目標解答時間 15分 配点 37点 15 次の英文を読み, 下記の設問 (A~D) に答えなさい。 Fire is "a good servant but a bad master." In my house, in summer, I smell the air for the faintest hint of smoke as keenly as any horse or dog or kangaroo. I watch for columns of smoke, visualising again and again how fire could rush( 1 )the hill towards us. But if you are philosophical about it, fire is a natural 5 part of the Australian environment and has been for millions of years. Living with the threat of fire in the bush, or in the wild, is like living with sharks when diving, or with snakes while walking, or with traffic accidents on a city street. The idea that we should remove every shark from the sea, or every snake from the land, and control- burn, or deliberately set fire, to prevent any risk of 10 bushfires is a recipe for making the environment even worse. As Phil Koperberg, head of the New South Wales Fire Brigades, said ( 2 ) the Sydney bushfires of 1994, amid calls for massive control burning, “Do you want to concrete over all the bush? If you choose to live in the bush, you choose to accept the risk. f It is often claimed that some Austratian plants and animals have actually adapted to fire, evidence of an extraordinarily long period (millions of years before human arrival) during which fire has been more significant in the Australian environment than it has been on any other continent, but this is probably not strictly true. Many plants have adapted to the environment in 20 ways that also happen to be valuable in times of fire. ( 3 ), animals have adapted to a variety of different habitats, and can therefore survive during different periods of vegetation regrowth after a fire (or after, say, a cyclone, a flood, or just a tree falling in a forest). A tree that has the ability to regenerate from roots or lower trunk when the 25 upper tree dies as a result of being broken off in a storm, or falls over, rotten to the core, will also be able to respond when the upper part is killed by a fire. Seeds adapted to long hot droughts, and requiring a combination of heat and water for germination", will also find a fire, if followed by rain, a good stimulus for growing new plants. There does appear to be evidence that chemicals in 30 smoke can help promote growth in plants, but whether this is a direct 可能性があるかを 何度も が続いているのだ。 森林地帯, ダイビングのときにサメ, そやカンガルーにも負けな の匂いを嗅ぐ。 私は,どのよ 暮らすようなものである。 海 しき主人である」( れば, 火事はオーストラリア >> のヘビを取り除くべきだと 意図的に火を放つべきだ , 1994年のシドニー ている真っ只中 と言った。 入れるこ

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英語 高校生

よろしくお願いします🙇‍♀️

1 国際学部 英語コミュニケーション学科 国際学科 適性テスト 60分 第1問 次の各文の1 10 に入る最も適切なものを、それぞれ①〜④の中から1つ選び、 解答欄の数字を マークしなさい。 解答欄には①~⑨までの数字及び記号があります。 間違った箇所をマークしないように 注意してください。 1. The researchers succeeded in filming the animal that 2 had seen Dhad been seeing 3. The institute will groups. stem from 4 occasions 2. Crops and plants did not grow well due to the extraordinary heat and lack of rainfall. This affected farmers' 3 triggers 2 vacancies Dincomes carry out 3 a survey to determine whether the government's economic policy has been beneficial across age 4. The organization calls for protecting foreign workers, many of who 2 whom 3 whose 7. The company released a set of rules announcements to customers. lasting (2) relieving . 5. The article suggests some training methods to eliminate unconscious 3 nutritions agreements recipes even though 1 before. had never been seen 2 proposal go off 10. Unless the countries reach a 1 distribution 7 10 (2) revenue 4 6. The author indicates that the growing popularity of DIY (Do It Yourself) is because of its 3 deadline potential symptom 8. The teacher allows students to use their electronic devices during the class, with them. only if 4 had never seeing 5 ) once have suffered abuse. 4 what 4 amount to based on race, gender and accents. 4 prejudices 6 accommodation gender-neutral language use in their advertisements, commercials, and 3 promising 8 2 for emotional healing. 4 storing 9. Some insist that the government should limit the time that children are allowed to use the Internet, while others oppose it. The 9 issue remains industrial 3 controversial 4 approval energy prices will surge and have a bad effect on citizen's lives. 3 prosperity they do not use social networking services 4 no matter how consensus REH

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