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英語 高校生

英検準一級の要約問題です。 添削していただけないでしょうか?🙇‍♀️

英検公式サンプル問題 ⚫ Instructions: Read the article below and summarize it in your own words as far as possible in English. ⚫ Suggested length: 60-70 words Write your summary in the space provided on your answer sheet. Any writing outside the space will not be graded. From the 1980s to the early 2000s, many national museums in Britain were charging their visitors entrance fees. The newly elected government, however, was supportive of the arts. It introduced a landmark policy to provide financial aid to museums so that they would drop their entrance fees. As a result, entrance to many national museums, including the Natural History Museum, became free of charge. Supporters of the policy said that as it would widen access to national museums, it would have significant benefits. People, regardless of their education or income, would have the opportunity to experience the large collections of artworks in museums and learn about the country's cultural history. Although surveys indicated that visitors to national museums that became free increased by an average of 70 percent after the policy's introduction, critics claimed the policy was not completely successful. This increase, they say, mostly consisted of the same people visiting museums many times. Additionally, some independent museums with entrance fees said the policy negatively affected them. Their visitor numbers decreased because people were visiting national museums to avoid paying fees, causing the independent museums to struggle financially.

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数学 高校生

どうして、底を2にするんですか??

重要 例題 38 ant = pa," 型の漸化式 | a1=1, an+1=2√an で定められる数列{an} の一般項を求めよ。 00000 【類近畿大 指針 がついている形, an² や an+13 など 累乗の形を含む漸化式 an 解法の手順は an+1=pa ① 漸化式の両辺の対数をとる。 an の係数かに注目して、底がりの対数を考える。 10gpan+1=10gpp+logpang すなわち 10gpan+1=1+glogpan 2 10gpan=bn とおくと bn+1=1+gbn → -logeMN = logM+log.N loge M=kloge M bn+1=bn+▲の形の漸化式 (p.464 基本例題 34 のタイプ)に帰着。 対数をとるときは, (真数)>0 すなわち a">0であることを必ず確認しておく。 CHART 漸化式 αn+1=pan" 両辺の対数をとる α=1>0で,n+1=2√an (>0) であるから,すべての自 解答然数nに対してan>0である。 よって, an+1=2√an の両辺の2を底とする対数をとると 10gzAn+1=10g22√an log2an+1=1+110gzan 2 bn+1=1+1/26n ゆえに 初 10gzan=bn とおくと これを変形して bn+1-2=(bn-2) ここで b1-2=10g21-2=-2 > 0 に注意。 厳密には,数学的帰納 で証明できる。 log₂(2.an) =log22+ log. 特性方程式=1+10 基本 α=2, (1) n (2) ar 指針 解答 よって, 数列 {b,-2} は初項 -2,公比 1/2の等比数列で n-1 b-2=-20 =-2(12) - すなわち bn=2-22- を解くと α=2 12 したがって, 10gzan=2-22 から an=22-22- \n-1 =21- logaan-pan-d 早 検 PLU anan+1 を含む漸化式の解法 実討 anan+1 のような積の形で表された漸化式にも 例えば 両辺の対数をとるが有効である。 LON

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