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数学 高校生

写真の問題の(3)についてですが、 なぜ「0<a<3」(上から3行目)という式をもちいてるのですか?この式がなくても他の3つの不等式を満たすようなグラフは題意を満たすグラフになると思うのですが… (言い換えると、「0<a<3」という式は必要条件?であるから不要なのでは?とい... 続きを読む

礎問 78 第2章 2次関数 45 解の配置 2次方程式 2-2ax+4=0 が次の条件をみたすようなαの範 囲をそれぞれ定めよ. (1) 2解がともに1より大きい. △〇 (2) 1つの解が1より大きく、他の解が1より小さいAO (3) 2解がともに0と3の間にある.△△ (4) 2解が0と2の間と2と4の間に1つずつある. 精講 解の条件を使って係数の関係式を求めるときは, グラフを利用しま す. その際, グラフの次の部分に着目して解答をつくっていきます。 あるxの値に対するyの値の符号 (1) ② 軸の動きうる範囲 ③ 頂点のy座標 (または, 判別式) の符号 このように, 方程式の解を特定の範囲に押し込むことを「解の配置」といい グラフを方程式へ応用していく代表的なもので,今後,数学ⅡIBへと学習が すすんでいっても使う考え方です。 確実にマスターしてください。 解答 f(x)=x2-2ax+4 とおくと, f(x)=(x-a)2+4-² よって, 軸はx=α, 頂点は(a, 4-α²) (1) f(x)=0 の2解が1より大きいとき y=f(x)のグラフは右図のようになっている. よって,次の連立不等式が成立する. f(1)=5-2a> 0 精講① 精講 ② ◆精講③ 次ページ右上の a>1 (4-a² ≤0 a</a/かつ 1 <aかつ 「a≦-2 または2≦a」 右図の数直線より、2≦a<mam -2 (a) 01 a y=f(x) IC 4-a² 25 a

未解決 回答数: 1
英語 高校生

()の中の答えを教えてください;;‪

7. I ( ) my success ( ) your advice. 私が成功したのは、あなたのアドバイスのおかげです。 8. I am ( ) an () to get up early. 私は早起きしようと努力している。 ) could you show me the way to the station? 9. I'm sorry to (b ) you, ( 御手数をおかけしてすみませんが、駅への生き方を教えてくださいませんか。 10. The girl (c) ( ) her mother about her lunch today. その女の子は母親に今日のお弁当のことで文句を言った。 11. He is quiet in class, but ()(), he is very lively outside of class. 彼は、授業中は静かだが、 それとは対照的に、授業以外ではとても活発だ。 12. I had to (c) ( ) my best friend in the speech contest. 私たちはスピーチコンテストで親友と競わねばならなかった。 13. This song () me () my high school days. この歌は私に高校時代を思い出させる。 14. The U.N. (s) the poor children ( ) food and milk. 国連は貧しい子供たちに食料と牛乳を供給した. 15. Most small children ( )(s) () dark places. ほとんどの幼い子供は暗い場所が怖い。 16. His ideas ( )(s) () mine. 彼の考えは私の考えと似ている。 17. What she said didn't ( )(s) () me. 彼女が言ったことは私には理解できなかった。 18. We must ()()() that mountain climbing is dangerous. 登山は危険だと心にとどめておくべきだ。 19. Smoking() (h) ( )your health. 喫煙は健康に害を与える。 20. ()()a (s), it began to rain. 突然、 激しく雨が降り出した。 (0) neleolus 21. Ⅰ ( )( )( ) homework all weekend. 週末はずっと、私は宿題で忙しかった。 INTERCY Lop Jamoszok 678038 201

解決済み 回答数: 1
数学 高校生

数学Aの確率の問題です。 127の(2)がどうしても理解できません。 まず、なぜ式変形をして1+4-n/n(n+6)になるのから始まり、そこから下に関しては精講を読んでもわかりませんでした! 教えてください!よろしくお願いします!

基礎問 127 確率の最大値 Pet 白玉5個、赤玉n個の入っている袋がある. この袋の中から、 2個の玉を同時にとりだすとき, 白玉1個, 赤玉1個である確率 をnで表すことにする. このとき, 次の問いに答えよ.ただし, n≧1 とする. (1) n を求めよ. を最大にする n を求めよ. 精講 条件に文字定数nが入っていると, 確率はnの値によって変化する ので,最大値が存在する可能性があります。 確率の最大値の求め方 は一般に,関数の最大値の求め方とは違う考え方をします.それは、 変数が自然数の値をとることと確率 ≧0であることが理由です。この考え方は、 パターンとして頭に入れておかなければなりません. その考え方とは次のようなものです.いま, すべての自然数に対して > 0 のとき, ある自然数Nで, n≦N-1 のとき, すなわち, n≧Nのとき, が成りたてば,nで表されている確率は, OSNO Pn+1>1 Pn pn+1 <1 Pn P₁<P₂<<PN> ÞN+1>...... が成りたちます。だからn=Nで最大とわかります. * LODED Pn+1 と1の大小を比較すればよいのです. ここで, pn Pn+1>1 Pn+1-Pn>0 Pn ですから、 Pn+1- 0の大小を比較してもよいのですが、 確率の式という のは、ふつう積の形をしていますので,わった方が式が簡単になるのです. (1) pn= 20 pn+1. Pn (2) .. 5C₁*nC₁ n+5C2 = 参考 ポイント 演習問題 127 pn+1−1= Pn 2.5.n (n+5)(n+4) 10n (n+5)(n+4) (n+1)(n+4) n(n+6). 10 (n+1) (n+5)(n+4) (n+6)(n+5) 10n よって,n<4のとき, 解 ·X 4-n n(n+6) 4-n -=1+- 1² n(n+6) n+11 Pn n=4のとき, Ds=pa 答 : D₁<P₂<P3<Þ4=Þ5> P6> Þr>...... よって, n を最大にするnは, 4,5 n≧5のとき,P+1<1 Pn AnCr=- 207 18S n! r! (n=r)! Pn+1の形で1と大 pn 小を比較 <n(n+6)>0 だから 符号を調べるには分 子を調べればよい 確率の最大値は,わって1との大小比較 この式をかく方がわ かりやすい この考え方は確率以外でも ① 定義域が自然数 ②値域 > 0 をみたす関数であれば利用できます。 たとえば,f(n=n(n+3) などです. この関数は n=2で最大になりま 2" すので、各自やってみましょう. ある袋の中にn個の白玉が入っていて、そのうち5個に赤い印 がついている. その袋から, 5個の玉を同時にとりだしたとき 2 一個の玉に赤い印がついている確率をpとおく. ただし, n ≧8 と する.このとき、次の問いに答えよ. (1) n をnで表せ. (2) を最大にするnを求めよ。

未解決 回答数: 1
英語 中学生

すべてわかりません…教えてください!

Unit 4 長文問題 もしも時間を戻せたら? 1 ) able to change the past? If you Do you ever wish you (1) had (2) that ability, maybe you would spend more time practicing soccer, learn the instrument that you always wanted to play, study harder for that big test, or try to save more money for the future. 2 What would you do if you had the ability to turn back the clock? This was a question which Mr. Woodall, a high school teacher in Philadelphia, asked his students. Mr. Woodall wanted to know what was important to his students but was pleasantly surprised to see the results. I think their answers will be very interesting to you, too. (3) 3 Mr. Woodall expected to see answers (which were connected to the own good of the students, but he was wrong. The majority of the answers (5)which he received from his students were for the good of others. 4 Targ ①関係 2157 (4) A very common answer he found was, “If I could turn back the clock, I would take back some things that I said to a friend." Apparently, many of the students regretted saying something (5) friends and wanted to change that. Surprisingly, close to 40% of the students answered this way. ) hurt their 5 Another common answer was about pets. "If I were able to turn back the clock, I would spend more time with my dog," or "(7)I would be nicer to my cat," were some common answers. Almost 25% of the students missed their pet very much and wanted to show more love. These pets included dogs, cats, birds, rabbits and other animals. 6 There were other answers about reading more books, studying harder, or eating less junk food. However, Mr. Woodall was quite impressed with his students and their concern for others. He decided to share all of the answers with his students, and the students enjoyed hearing the different answers. Mr. Woodall decided to try this activity with his students every year. By asking, he felt he would learn a lot about his students. tu P e g n t

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英語 高校生

教えてくださる方お願いします!!至急です!! 長文が苦手で教えてください

26 Unit 4 長文問題 もしも時間を戻せたら? 1 Do you ever wish you ( ) able to change the past? If you had (2) that ability, maybe you would spend more time practicing soccer, learn the instrument that you always wanted to play, study harder for that big test, or try to save more money for the future. 2 What would you do if you had the ability to turn back the clock? This was a question which Mr. Woodall, a high school teacher in Philadelphia, asked his students. Mr. Woodall wanted to know what was important to his students but was pleasantly surprised to see the results. I think their answers will be very interesting to you, too. 3 Mr. Woodall expected to see answers (which were connected to the own good of the students, but (3) he was wrong. The majority of the answers (5)which he received from his students were for the good of others. 4 A very common answer he found was, "If I could turn back the clock, I would take back some things that I said to a friend." Apparently, many of the students regretted saying something (5) ) hurt their friends and wanted to change that. Surprisingly, close to 40% of the students answered this way. 5 Another common answer was about pets. If I were able to turn back the clock, I would spend more time with my dog," or "I would be nicer to my cat," were some common answers. Almost 25% of the students missed their pet very much and wanted to show more love. These pets included dogs, cats, birds, rabbits and other animals. 66 6 There were other answers about reading more books, studying harder, or eating less junk food. However, Mr. Woodall was quite impressed with his students and their concern for others. He decided to share all of the answers with his students, and the students enjoyed hearing the different answers. Mr. Woodall decided to try this activity with his students every year. By asking, he felt he would learn a lot about his students. Target ①関係代名詞 ②仮定法・間接疑問文 turn back (時計を) 巻き戻す pleasantly 心地よく expected to 〜するだろうと思う good majority , t take back 取り消す apparently どうやら~らしい close to 〜近く be nice to 〜にやさしい concern for 問1 (1) ( 〜への気遣い配慮 Pag 2 junk food ジャンクフード 問3 い。 ( 問 問 (4) (6) 1

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英語 中学生

すみません、至急お願いします。 問1から問9まで教えてください🙇‍♀️

Unit 4 長文問題] もしも時間を戻せたら? ) able to change the past? If you 1 Do you ever wish you (2) had that ability, maybe you would spend more time practicing soccer, learn the instrument that you always wanted to play, study harder for that big test, or try to save more money for the future. 2 What would you do if you had the ability to turn back the clock? This was a question which Mr. Woodall, a high school teacher in Philadelphia, asked his students. Mr. Woodall wanted to know what was important to his students but was pleasantly surprised to see the results. I think their answers will be very interesting to you, too. Hou 3 Mr. Woodall expected to see answers (which were connected to the own good of the students, but (3) he was wrong. The majority of the which he received from his students were for the good of answers (う) others. Target ① 関係代名詞 ②仮定法・間接疑問文 66 4 A very common answer he found was, “(4)If I could turn back the clock, I would take back some things that I said to a friend.” Apparently, many of the students regretted saying something (5) friends and wanted to change that. Surprisingly, close to 40% of the students answered this way. 7) hurt their 5 (7) (6) Another common answer was about pets. "If I were able to turn back the clock, I would spend more time with my dog," or "I would be nicer to my cat," were some common answers. Almost 25% of the students missed their pet very much and wanted to show more love. These pets included dogs, cats, birds, rabbits and other animals. turn back and M (時計を) 巻き戻す pleasantly 心地よく expected to 6 There were other answers about reading more books, studying harder, or eating less junk food. However, Mr. Woodall was quite impressed with his students and their concern for others. He decided to share all of the answers with his students, and the students enjoyed hearing the different answers. Mr. Woodall decided to try this activity with his students every year. By asking, he felt he would learn a lot about his students. 〜するだろうと思う good majority , t take back 取り消す apparently close to どうやら~らしい t be nice to 〜にやさしい de 問 1 (1) ( 問2 問3 い。 1.9 ( junk food ジャンクフード concern for . 〜への気遣い、配慮 (4

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