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英語 高校生

青で線を引いた部分の文の構成がわかりません。文の要素の説明して欲しいです🙇‍♀️

will interest anyone who has recently attendeda class reunion - or plans to. Bahrick and 記憶」に関する英文だよ。パラグラフごとに内容を確認しながら読んでみよう。 the 1970s, the noted psychologist Harry Bahrick conducted a landmark study th. Is "colleagues asked hundreds of former high school students to look back at th yearbooks and see whether they could remember the faces of their classmates. What tho 5 discovered is (ア)proof of the power of human memory. For decades after graduation t. memory of fofmer students for the faces of their classmates was nearly undamaged. Evos after nearly half a century had passed, the former students could still recognize seventw three percent of faces of their classmates. But when it came to names, Bahrick found, memories were much worse; after nearly fif.. 10 years the former students could remember only eighteen percent of their classmates names. Names, for whatever reason, donot stick very well in our memories, or they stick only partway, causing us to call our brother-in-law Bob, Rob, or to mistake the author Ernest Hemingway for the actor Ernest Borgnine. Why should we remember faces, but not the names that go with them ? Part of the answer 15 is that (イWhen it comes to memory, meaning is king, Our long-term memory, even for things we've seen thousands of times, is limited. It is prúmarily *semantic, which means that in most daily instances of.remembering what_we mist recallis meaning, not surface details. Take the common *penny, for instance. How well do you think you can remember its features ? In a well-known test, two researchers, Raymond Nickerson and Marilyn Adams. 20 asked just such a question. The answer they got surprised them - and may surprise you. In the test, Nickerson and Adams asked twenty people to do something that sounds really easy: from memory, draw the front and back of a penny. After the drawings were done, Nickerson and Adams graded them to determine how accurately the participants had drawn eight critical features, like the placement of Lincoln's profile on the front of the coin 25 and the placement of the Lincoln Memorial on the back. The results wereA Of the twenty people tested, only one - an *avid penny collector 一 accurately recalled and located all eight features. Of the eight features, the average number recalled and located correctly was just_three. Interestingly, the most frequently forgotten feature was 30 the word “LIBERTY," which appears on the front of the coin, to the left of Lincoln's profile. The findings from the penny-drawing test were conducted a series of follow-up tests to try to confitm what was going on here. Among othe= things, they wondered: If people couldn't recall exactly what a penny looks likeg would the (at least be able to tell the real thing from a fake ? To find out, they showed a new group of people fifteen drawings of the heads side of penny. Only one of the drawings was accurate; the rest were not. The participants' job w to pick the right one. Again, the results were disappointing. the right one. NT ONTO POINT B |enough that Nickerson and Adam: POINT C than half of the people in the study picls (51 注)*colleague =同僚 *vearhook 京竜アル

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数学 高校生

(2)の問題は特性方程式の解が1と2であることを利用して、写真のように解くのは大丈夫ですか?ちょっと雑ですみません。

530 第8章 数 (1) an+2-2am+1-15a,=0 ……① が an+2-ean+1=B(an+1- aan)……2と変形で *ル-1 bn=dn+1-an とおくと,数列{bn}は数列 {an} の (1より =0 列 Unt 3 漸化式と数学的帰納法 Check 531 例 題 300 隣接3項間の漸化式 (1) 2-3an+1+2an 0より、 an+2-an+i=2(an+1-an) ..の 次のように定義される数列 {an}の一般項 an を求めよ。 (1) a=1, az=2, an+2-2an+1-15am=0 (2) a=3, az=5, an+2-3am+1+2an=0 (x-1)(x-2)3D0 より、x=1, 2 階差数列であり,②より, a=1, B=2 で考える。第8章 bn+1=2 b。 つまり,数列(bn} は、 初項 b=a2-a=5-3=2 公比 2 考え方(A) 特性方程式の解 a, BがαキB となる場合(p.529)である の等比数列であるから, bn=2-27-1 きたとする。 2より, antaー(a+B)an+1taBa,=0 bn=2" とできるが, [a=-3 {8-5 これより, a+8=2, aB=-15 だから, | anta+3an+i=5(an+1+3am) lamtz-5am+1=ー3(an+1-5am) または Q=5 したがって, n2のとき, -1 B=-3 こb。を計算するので an=a」+E。 =1 k=1 bn=2-2"-1 のままの方 が間違いが少なくなる。 {an} の階差数列{ba n22 のとき よって,2より, 1-1 =3+ 22-2*-1 これより,一般項 anを求めればよい。 (2)(A) aキ8 において, とくに α=1 となる特別な場合である。 つまり, k=1 2(2"-1-1) ag+2-3am+1+2an=0 は, an+2-Cn+1=8(an+1-an) 数列(a+-)は(a)の階差数列である。 =3+ {a)の階差数列 2-1 =3+2(2"-1-1) =2"+1 -1 an=a+ 2b。 {an+1-a) となり、 (1)と同様に解くこともできるが,ここでは階差数列の 考え方を使って解いてみよう。 =1 n=1 のとき, a=2'+1=3 となり成り立つ。 m n=1 のときを確認 よって, an=2"+1 ュ-15am=0 Tan+3a のより x-2x-15=0 w 解答 (aneit3an) (x+3。 E Rocus

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