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数学 高校生

黄色いところは何をやっているのか分かりません。。(;;)教えて欲しいです!

重要 例題 160 媒介変数表示の曲線と面積(2) 媒介変数によって, x=2cost-cos2t, y=2sint-sin2t (0≦t≦) と表される右図の曲線と, x軸で囲まれた図形の面積Sを求めよ。 YA x 基本156 CHART & SOLUTION 基本例題156では,tの変化に伴ってxは常に増加したが, この問題ではの変化が単調でないところがある。 y Y2 右の図のように, t=0 のときの点を A, x座標が最大とな る点を B(t=to で x 座標が最大になるとする), t=πのと きの点をCとする。 S B A -3 O 1₁ x Xo この問題では点Bを境目としてxが増加から減少に変わり, 軸方向について見たときに曲線が往復する区間がある。 したがって, 曲線AB を y, 曲線 BC を y2 とすると,求め る面積Sは t=π t=0 ●t=to 曲線が往復 している区間 s=Sydx-Sy yidx と表される。 よって、xの値の増減を調べ, x座標が最大となるときのtの値を求めてSの式を立てる。 また,定積分の計算は、置換積分法によりxの積分からtの積分に直して計算するとよい。 解答 図から, 0≦t≦↑ では常に y≥0 また y=2sint-sin2t=2sint-2sintcost =2sint(1-costするど よって, y=0 とすると sint=0 または cost=1 24 0≤t≤ x 5 t=0,0-(D)\\ 次に, x=2cost-cos 2t から 7 dx =-2sint+2sin2t dt xh (bala-nia) Daia inf. 0≤ts D sint≧0, cost ≦1 から y=2sint(1-cost)≧0 としても,y≧0 がわかる。 455-25 =-2sint+2(2sintcost)_(n)\ =2sint(2cost-1) 0<t<πにおいて dx dt -= 0 とすると, sint>0 で あるから π t 0 π |3| cost= 201 ゆえに dx t= J3 dt + よって、xの値の増減は右の表のようになる。 x 1 →>>> 032 ↑ P -3

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英語 高校生

線を引いた部分について 意味的には100ドルを支払えますか?みたいな感じだと思うのですが、なぜstretchなのかわからないです。stretchの意味を調べましたがそのような意味はないと思いました。これは話の流れで理解するものなのでしょうか?

4. 解答用紙を折り曲げたり、 破ったり、また汚したりしないでください。 Antiqminishes boodie alle gu [I] A. 次の会話文の空所 (1)~(5)に入れるのに最も適当なものをそれぞれA〜Dか ら一つずつ選び、その記号をマークしなさい。 nwomin Aika is an exchange student visiting her university's medical center. aliquab G Receptionist: Hello, how may I help you today? Aika: 19bnu Um, I'd like to see a doctor, please. lobus A (8) (1) Receptionist: Certainly. Is this your first visit here? plent Aika: Yes. (2) Receptionist: Then could you please show me your student ID and fill in this form? Aika: Sure. Hmm, I just have a couple of questions about the form. I don't have a mobile phone yet, so what should I put for the phone number? (3) Receptionist: No problem. Aika: And I haven't got a reference number for my medical insurance yet. Receptionist: Well, if you don't mind paying in cash this time, the insurance company will pay you back later. Aika: I don't have a lot of money on me. (4) Receptionist: The full price is about $100. Can you stretch to that? Aika: And a final question-under (5) "current medication," should I include the Chinese herbal tea I drank this morning? Receptionist: Absolutely. The doctor will want to know about that. even (1) A. Could you tell me what they look like? RENA[I B. Can you let me know where I can find one? - C. I've got a terrible stomachache. D. You look like you're in pain. om dan wood one damele batelas Yood bas att rafio el to smo sval of broot saw has ow gr(2) A. I'm so excited to be here. ede, B. I've just started my courses. sobiro ni C. My work here begins today.no ai rad bertD.I'm sorry I didn't visit sooner. Jus Teris auomal guidoned not eldiamoques legal bele saw ad? 8891 (3) A. You can leave that blank for now.uldn't best aid ea find at etoned blow bename Jedi broco 19 oved B. You can use my phone instead. deb a a mood eva C. You can buy one here right now.sed airmailqmens D. You can write any number you like. Thesisng Dia 16M AJ beate-owd limonu od taustasted to our yana(4) A. I gave most of it to the insurance company, of in Wila to odoriq B. I think doctors are rich enough already. IM ser osobinal quodblA C. What special deals do you have this week? ani i Ted toode D. How much will it cost to see a doctor?sil a'mi nio (5) A. If you help.alq at alex sgud a bad sale sing a toll ow odni B. I think so.ew mos voso as vltam) C. I exercise daily. so ed bongings to d tado got n D. That's easy!omberg-bang of sh saisius has (ma gained a suo ad size does an hot blow B ban 01 nowwted bags wat bewoldt ST! al galain bootevbA ada ad quos how all of unir containing herbe still ge-2() g) <-2-

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英語 中学生

答えはイなのですが、アが×な理由が分かりません。 教えてください。

7 次の(1),(2)の英文を読んで、それぞれの問いに答えなさい。 (1) みなみ市 (Minami City) に住むユイ (Yui)とジョン(John) は、 留学について調査し, 英語でプレ ゼンテーション(presentation) を行いました。 ユイがスライド (Ade)を使って発表をしています。 Hello, everyone. Are you interested in studying abroad? Zealand to study English last summer. I went to New It was an amazing experience for me during those ten weeks. I believe that studying abroad is very meaningful for high school students. Now, please look at Slide 1. It shows the number of Japanese high school students studying abroad from 2009 to 2019. The number went down once in 2015, but in 2017, the largest number of students, more than 45,000, studied abroad. In 2019, the number went down a lot because of big international problems, but we believe that more students will study abroad in the future. So, where did many students go? Look at Slide 2. It shows the countries that the high school students in Minami City went to from 2009 to 2019. We can see that more than half of the students went to English-speaking countries This means that many students used English during their stays. I think that we can improve our language skills by communicating with local people a lot. For example, before studying at a English, but my English (Ave school in New Zealand, I wasn't very good at improv after staying there. But studying abroad isn't easy for everyone. Having friends from abroad is good, but not everyone has that chance. So, how should we study English in Japan? We asked 500 students at this high school, "How do you study English at home?" Look at Slide 3. It shows the results. Among these several ways, we recommend watching movies and TV dramas in English. We think so because by watching them, we can also learn about the people living there and their cultures. Learning these things is as important as learning the English language itself. We think that learning English is very useful for high school students. Study hard, and if you have a chance, please go abroad and learn many things. Slide 2 Slide 3 Ways to Study English % 25% 32% Study with textbooks 62 Watch movies 14 10% Watch TV dramas 14 15% Read English books or newspapers 7 U.S. U.K. Australia ☐ others South Korea Keep a diary in English 3 (注) meaningful 意味のある English-speaking 英語を話す not everyone U.S. アメリカ合衆国 South Korea すべての人が〜とは限らない chance U.K. keep a diary 日記をつける itself それ自体

解決済み 回答数: 1