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英語 中学生

根気強く英文読める方お願いします🙏 この問題の(2)は合っているでしょうか。 違うのなら違う理由も教えてくれるととても嬉しいです😭お願いします

TREK [3] 9分 10 2935 受験 難問 次の英文を読んで、あとの(1)~(3)の問いに答えなさい。('13 神奈川県) Brian is a high school student from America. He joins a *volunteer club at school. Last Sunday he went to a "nursing home with his friends to teach the old people living there about computers. Mr. Doi, one of the old people there, is talking with Brian in a room at the nursing home. sdgoon 5 Mr. Doi: Hello, I am Kazuo Doi. Nice to meet you. Thank you for coming today. Nice to meet you, too. My name is Brian. What can I do for you, Mr. Doi? Brian Mr. Doi: Can you teach me how to send e-mails, Brian? Brian Mr Doi : Brian Of course, I can. Do you want to send an e-mail to anyone? Yes. One of my friends lives in a nursing home in Hokkaido. I have not seen her for a long time, but she sent me a "postcard last summer. She wrote her *e-mail address on the postcard. I want to send her an e-mail to say "Hello," but I don't know how to do it. salad : Don't worry, Mr. Doi. It is not difficult to send an e-mail. Tellsafi Two days later, Brian and his friend Yumi are talking in their classroom. 15 Yumi Brian Yumi Brian : 20 Yumi : Brian, I hear you went to a nursing home last Sunday, right? : Yes. I went there to do *volunteer work with my friends. : That's great. What did you do there? odon of d We taught the old people living there about computers. They were very glad to learn how to use computers. What did you teach them about computers? I taught some old people how to send e-mails. Mr. Doi was one of them and Brian : his English was good. Read this e-mail from him. He sent it to me yesterday. Brian and Yumi are reading the e-mail from Mr. Doi. Hello, Brian, 100 living here enjoy it. I am sending this e-mail with a picture of me *in front of a microphone." Her e-mail was *encouraging to me. Now I have found an important thing to me. It is to try new things. When I find a new thing to try, I will send you an e-mail again. 35 Kazuo Doi After reading the e-mail from Mr. Doi, Yumi and Brian are talking again. Yumi Mr. Doi enjoys *communication by e-mail. Brian Yes. I'm very happy to hear that. Yumi You did a good thing, Brian. 40 Brian Yumi Brian 45 Yumi : Brian Yumi 50 Brian Yumi 55 Brian T Thank you for coming last Sunday. Do you remember my friend who sent me a postcard with her e-mail address? After I sent her an e-mail, she sent me an e-mail back soon. Using e-mail is a lot of fun. In her e-mail she said, "Now I am trying a new thing in my nursing home. I am *in charge of an announcement over the PA system for 10 minutes in the morning. During this time, I read the *newspaper of the day and make some *comments. Many people Yumi Thank you, Yumi. I went to the nursing home to teach the old people there about computers, but I also learned something there. : What is it, Brian? Mr. Doi knew his friend was in charge of an announcement over the PA system, and then he started to think about trying a new thing, too. I know. Mr. Doi says, "encouraging" in his e-mail. Right. When I taught him how to send e-mails, he said, "I have wanted to learn a lot of things. Using e-mail is one of them." I see. You want to say the e-mail from his friend made him more *positive, right? That's right. First, Mr. Doi learned how to send e-mails and wrote an e-mail to his friend. Next, he got an e-mail from his friend and knew his friend was trying a new thing. Now Mr. Doi ( ) to him. Mr. Doi thinks that it is to try new things. We can say it is good to know how our friends are doing. It is wonderful to *communicate with other people, Brian. : I think so, too. Communicating with other people can make people more positive. I learned that from volunteer work in the nursing home. : I hope that Mr. Doi can find a new thing to try. Please tell me when you get an e-mail from him again. (注) volunteer club ボランティアクラブ nursing home 老人ホーム send〜 〜を送る postcard 絵はがき e-mail address 電子メールアドレス (約 685 語) volunteer work ボランティア活動 in charge of an announcement over the PA system 館内放送を担当して comments コメント in front of a microphone マイクの前の communication by e-mail 電子メールによるコミュニケーション communicate with ~ ~とコミュニケーションをとる newspaper encouraging 励みになる positive 前向きな

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数学 高校生

模範解答のように、場合わけしなかったんですけど、(写真2枚目)これでもオッケーですかね???

00 重要 例題 102 2次方程式の共通解 2つの2次方程式2x2+kx+4=0, x2+x+k=0がただ1つの共通の実数解をも つように定数の値を定め、その共通解を求めよ。 基本 97 171 "DX=RB 323 -z 指針 2つの方程式に共通な解の問題であるから,一方の方程式の解を求めることができ たら,その解を他方に代入することによって、定数の値を求めることができる。しか②xxc- しこの例題の方程式ではうまくいかない。 このような共通解の問題では,次の解法 が一般的である。 119. 1 式を解く。 D>0 D=00 えるのは 一般に2つの解をもつから、“同じだということを示す 2つの方程式の共通解を x=αとおいて、それぞれの方程式に代入すると ①, a2+α+k=0 ② sak 2a2+ka+4=0 これをαkについての連立方程式とみて解く。 ②から導かれる k=--α を 1 に代入(kを消去してもよいが, 3次方程式と なって数学Ⅰの範囲では解けない。 この問題では,最高次の項であるの項を消去す ることを考える。 なお, 共通の 「実数解」 という問題の条件に注意。 +x+k 1 3章 1 2次方程式 CHART 方程式の共通解 共通解を x=α とおく 2x ただ交点 共通解を x=α とおいて, 方程式にそれぞれ代入すると 式を解く 2a2+ka+4=0 ①, a2+α+k=0 解答 ①-② ×2 から (k-2)a+4-2k=0 α2 の項を消去。 この考 ↓ ゆえに (k-2)(a-2)=0 よって k=2 または α=2 を加減法で解くことに似 ている。 実数解 ずに [1] k=2のとき ら 2つの方程式はともに x2+x+2=0 となり, この方程式 数学Ⅰの範囲では, の判別式をDとすると D=12-4・1・2=-7 D<0 であるから,この方程式は実数解をもたない。 ゆえに2つの方程式は共通の実数解をもたない。 x²+x+2=0の解を求め [2] α=2のとき ②から 22+2+k=0 よって k=-6 このとき2つの方程式は2x26x+4=0, x2+x-6=0 すなわち 2(x-1)(x-2)=0, (x-2)(x+3)=0 とな り,解はそれぞれ x=1,2; x=2, -3 ることはできない。 x1=2 =2を①に代入しても ↑ よい。 ただまが同じ ってだけ よって、2つの方程式はただ1つの共通の実数解 x=2 をもつ 以上から k=-6, 共通解はx=2 注意 上の解答では, 共通解 x=α をもつと仮定してαやんの値を求めているから 求めた値に対して,実際に共通解をもつか,または問題の条件を満たすかど うかを確認しなければならない。 練習 2つの2次方程式 x2+6x +12k-24=0, x2+(k+3)x+12=0がただ1つの実数を 102 共通解としてもつとき,実数の定数kの値は ]であり,そのときの共通解は である

解決済み 回答数: 1