例121 (3)何故このように場合分けするのですか？　幅？についても何か教えていただきたいです

★★☆☆ 特講 例題 121 ガウス記号を含む方程式 次の方程式を解け。 ただし, [x] は x を超えない最大の整数を表す。 (1)[2x] = 3 (2) [3x-1] = 2x (3) [2x]-[x] = 3 ★★★☆ (1),(2)はガウス記号が1つ [x]=nのとき n≦x<n+1 として外す fic Action ガウス記号は,n≦x<n+1 のとき [x] = n として外せ 例題120 (3)はガウス記号が2つ 場合に分ける [x] => -1 [2x] 48217=2 幅1ごとに値が変わる 一般にこの部分で考えてみる 3 1 2 n 4/1/2n+1 幅 ごとに値が変わる (ア)(イ) 思考プロセス 3 2章 2次関数と2次不等式 (1)[2x] =3より,3≦2x <4であるから 32 (2)[3x-1] = 2x. ① より, 2x は整数である。 ①より 2x3x-1 <2x+1 ≦x<2 。 これを解くと 1≦x<2 4 22x4 であり, 2x は整数より 2x=2,3 3 よって x=1, 2 (3) [2x]-[x] = 3 ・② とする。 方程式の解は,不等式で 表される範囲になる。 [3x-1] は整数である から 2xも整数になる。 2x3x-1 より x≧1 |3x-1<2x+1 より x<2 (ア) n≦x<n+ 1/2(nは整数)のとき 2n≦2x<2n+1 であるから [2x] = 2n また,[x] = n であるから,②は2n-n=3 よって n=3 ゆえに 3≦x< x</ xを幅 1/2で場合分けす る。 (イ) n+ 12/2≦x<n+1(nは整数)のとき 2n+1≦2x<2n+2 であるから [2x]=2n+1 また,[x] = nであるから,②は (2n+1)=3 よって n=2 5 ゆえに ≦x<3 2 5 (ア)(イ)より ≤x< 2 2 121 次の方程式を解け。ただし、[x]はxを超えない最大の整数を表す。 (1) [3x] =1 (2) 2x=[√5] (3) [2x+1]=3x (4) [3x]-[x]=1 217 222

209 (3)について、I行目は理解できるのですが、2行目以降がわかりません

★★☆☆ 組合せは何 場合 例題 209 整数解の個数 次の条件を満たす整数の組 (x, y, z) は何組あるか。 (1)x+y+z= 7, x ≧ 0, y ≧0, z≧0 (2)x+y+z= 7, x ≧ 1, y≧1, z≧1 01★★ ★★★☆ 6 章 15 順列と組合せ → a, a, b, c ◆a, a, a,c → b, b, b, b す の =2 (個) 必要 思考プロセス (3)x+y+z≦ 7, x ≧ 0, y ≧0, z≧0 既知の問題に帰着 (1)7を3つの整数x,y,zに割り振る。 ⇒ 7個のものを3種類に分ける。 ⇒7個のを2個の(区切り)で分ける。 (例題 208 に帰着) (1)･･ ...x, y, z はすべて 1以上 ⇒先にx, y, zに1つずつ0を割り振ってしまい, 残り4つの ○ の x,y,zへの割り振りを考えればよい。 対応 (3) 不等式の場合には、001000121わない 右のように対応させる。 001000010 y 対応 (x,y,z) = (2,4,1) ↓↓ (x, y, zに xyz割り振る (x,y,z)=(2,3,1) Action» 係数が等しい不定方程式の整数解の個数は、重複組合せで考えよ A (1) 求める組の総数は7個の○と2個のの順列の総数 に等しいから 9! 7!2! =36 (組) を合わせた ■場所から を選ぶと 15(通り) (2)求める組の総数は, 7個の○と2個のに対して, まず,3個の○を1個ずつx, y, zの値に割り振ると考 えると,残り4個の○と2個のの順列の総数に等しい =15 (組) から 6! 4!2! nHr (別解 合わ 50 含 つの箱だけに入 求める組の総数は7個の○に対して,間の6か所か ら2か所選んでを入れる入れ方の総数に等しいから 62 = 15 (組) (3)求める組の総数は7個の○と3個のを1列に並べ 1つ目のより左側の○の個数をxの値, 1つ目のと2つ目のの間の○の個数をyの値, 2つ目のと3つ目のの間の○の個数を2の値 とすると考えて 10! = =120 (組) 7!3! 209 次の条件を満たす整数の組 (x, y, z) は何組あるか。 (別解 x, y, zの3種類のもの から重複を許して7個と る組合せの数であるから 3H7=3+7-1C7=9C7=9C2 36(組) ○|○○○」のとき x=1+1=2 y=3+ 1 = 4 z=0+1=1 2個ので区切られた3 つの部分には少なくとも 1個の○が含まれる。 7-(x+y+z)=u とおくと x+y+z+u=7 x≥0, y ≥0, z≥0, u≥0 を満たす整数の組の個数 を求める問題となる。 は何 208 (1)x+y+z=8,x≧0, y≧0, z≧ 0 (2)x+y+z=9,x≧1, y ≧1, z≧1 (3)x+y+z=10,x≧0y0z≧0 381 p.391 問題209

英単語を覚えるにあたってどうしてもローマ字読みに変換して覚えてしまうのですがあまり良くないですよね︎；； 例えばTimeであれば 「ちめ」のようにすごく不規則なんです！ 皆さんはどのようにして英単語を覚えていますか？よろしければ教えて下さい

鍵カッコのしてあるところを翻訳機を使わずに日本語訳に直して欲しいです🙇‍♀️🥶 お願いします😓

6 Reyhan Jamalova is one of those people. Reyhan is a student in Azerbaijan. When she was fifteen, Reyhan invented a device to make electricity from rain. Reyhan's device can power 22 LED lamps for 50 seconds. Each device uses only 7 liters of rainwater. Its battery can store power to use later. Reyhan says she created the device to help poor people, especially in rainy countries. Her device is not expensive. It does not even need power lines. It can help many people get electricity. 7 Is there anything you can do for a sustainable energy future? As a consumer, you can decide how much electricity you use. You can also decide what kind of energy you want to use. You may even be an inventor, like Reyhan. Your actions are important. What can you do to make your energy future brighter?

ここの回答は、Because they will carry pollen to flowers like bees.で正解なのでしょうか？

Why will the bee robots be useful in agriculture?

この問題の②イ③カなのですがどうしてこの答えになるのですか？

2 ① 43% 40% 3 31% 次の英文は, 南アメリカの先住民に伝わる, クリキンディ (Kurikindi) という名前のハチ ドリ hummingbird) の短い物語を題材に書かれたものです。 (①)~(③)に 最もよく当てはまる語を,それぞれ下のア~カから1つ選び, 記号で答えなさい。 <宮崎県改気 I'd like to introduce a short story of a hummingbird. A hummingbird is a very little bird. The little bird's name in this story is Kurikindi. Kurikindi lived in a forest. One day there was a * fire in the forest. The little bin stayed there and tried to *put out the fire. But all the other animals hurried to *escape. When they saw Kurikindi on the way, they asked Kurikindi, “Why are you doing that?" Kurikindi answered, “I'm only doing something I can do." After ( ① ) this short story, I thought about a few things. For example, did the hummingbird believe he could put out the fire? Why did all the other animals want to escape from the forest? Kurikindi did (②) so small that others thought his *actions meant (③). Many people often think like that. What do you think about Kurikindi? * fire (火事) put out (消す) escape (逃げる) action (行動) ア read イ something ウ reading I came オ excuse カ nothing 動物は いであ はクリ 3 Alt 文にな に bel 分詞と 多く とされ stops 停」と 意味が が競 を選 (要約) 私の 催され 私の女 国人 に駅に い 私は

答えがなく分かりません お願いします

I'm from Mexico. You're from Brazil. He's from Japan. She's a business student. It's an exciting city. We're in the same class. They're my classmates. 1. 2. 3. actions of be I am Nagoya. I'm you're = you are he's = he is she is it is she's it's we're = we are they're they are A Complete these sentences. Then tell a partner about yourself. My name is Aiko Yoshida. = Possessive adjectives brother is a college student. name is Matias. sister is a student here. our their GRAMMAR PLUS see page 132 my your his her its from Japan. from Santiago. Angelica, but everyone calls me Angie. a student at City College. in Las Vegas. family is in name is Haruki. a really nice city. parents are in Chile right now. last name is Newton. parents are on vacation this week.

大至急!! 入試問題です! 添削お願いします!

LUI Y, why did Kukai throw a Buddhist tool? U0 WIl OIu AccofUllIg Kovasan, there are many good places to visit in Japan. Where do you want to go'? ite the place first, and give two reasons. へ )() 25 ) 35 e

こちらの答えを教えていただきたいです。 お願いします；；

教科書と似たテーマの文 イ次に 地球温暖化 (global warming) についての文章を読もう 2 次の英文を読み,あとの問いに答えなさい。 STEP Today we sometimes have big typhoons and water shortages in the world. Scientists say that these come from global warming. According to research, 1 the average temperature is 0.78℃ higher than it was 100 years ago. Because of this, many problems happen all over the world. For example, the, lands,of Some countries started sinking because the sea level is rising., People in other countries can't harvest(bese it hasn't rained for a long time. 5 上 する To solve these problems, many countrieshave taken action. In 2015, they had a meeting in Paris and decided to work together on climate change. Japan also joined the meeting, and decided to reduce the amount of CO, by 26% compared to 2013 by 2030. 9 (注)typhoon 台風 rain 雨が降る shortage 不足 average temperature 平均気温 harvest 収穫する Paris パリ reduce 減らす CO, 二酸化炭素 compared to と比べて (1) 本文中の下線部の例としてあげられていることを,日本 語で2つ書きなさい。 (2) 本文の内容に合うように, ( )に適する語を書きなさい。 Scientists say that the ( (5点×7) 2思判·表 10点×7 || 0 ab t1ot くつかの国の土地は歌み行めていると、 ) for big typhoons の側の人をは収稿できないをと A and water shortages is global warming. A B The average temperature 100 years ago ) higher than it is today. (3) 温暖化に対する日本の取り組みを次のようにまとめまし に適する日本語を書きなさい。 年にパリでの会議に参加し, 対応を表明した。具体的には, 2030年までに二ニ酸化炭素 B a た。 a (3) D 量を 2013年比で ことを決定した。 の

これの（②）に一語を文章から抜き出していれるんですけど、quickはだめですか？ 答えはearlyでした。

When I first moved to Japan, my new life was like an adventure, and full of surprises. Ive forgotten a lot of small things, but I'll never forget the first party I gave. 1was teaching English at a university in Japan. I decided to have a party for some Japanese students at my apartment which was near the school. The party was at 7:00. I was rushing to get ready, cleaning the room, checking the food, and so on. And finally at about 6:45, I was about to take a quick shower and get dressed. Perfect timing, I thought. But just then, the doorbell rang. The students, in one big group, were already at my door! In America nobody comes early, and in fact, most people come a little late on purpose, usually alone or in pairs. We call Oit being “fashionably late." I had to ask them to wait outside for about 15 minutes. “The party starts at 7:00!" I said, This was a real life lesson for them and for me about cultural differences. They learned they should not come to my parties ( ② ) again, and I learned I should be ready a little (2 )just.in.case. So at 7:00, everyone came in, with my second surprise. ③They showered me with all kinds of presents! I was happy to get so many presents, of course, but I really didn' t want them to come together. I was very busy because I had to find vases for the flowers, bowls for the snacks, and try to say Thank you' for their gifts. People usually take something likea bottle of wine to an American-style party. But I felt. more. appreciated by my_guests in Japan. It was more like my birthday or Christmas than a simple homeparty. FinallyI sat on the sofa and talked with them. Everyone was having a good time. Though I have lived in Japan for more than ten years, I m still surprised at many things. Life is full of surprises.