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Mathematics Senior High

このマーカーで引いたところって、Q中心の半径1の円で-2t分回転させたからこのような座標隣っているのですか?

重要 例題 287 曲線の長さ (2) 円C:x+y2=9の内側を半径1の円Dが滑らずに転がる。時刻 t において D は点 (3cost, 3sint) でCに接している。 (1) 時刻 t=0 において点 (3,0)にあったD上の点Pの時刻t における座標 (x(t),y(t)) を求めよ。ただし, 0≦t≦πとする。 2 X(2) (1) の範囲で点Pの描く曲線の長さを求めよ。 [類 早稲田大〕 基本286 指針 (1) ベクトルを利用。 PはDの円周上にあり, Dの中心Qとともに動く。 そこで OP=OQ+QP (Oは原点)として, QP をもの式で表す。 Q, 毎日 円x2+y2=2(x>0)の周上の点Pの座標は (rcost, rsint) で表され,このとき OP がx軸の正の方向となす角はtである。 dx (2) p.465 基本事項 ① S. √ (d) + (a)* dy Ja V dt dt 解答 (1) A(3, 0), T(3 cost, 3sint) 3. 00107: DとCがTで接しているとき, Dの中心Qの座標は (2cost, 2sint) である。 また, TP=TA=3tである から,x軸の正の方向から半直線 QP への角は t-3t=-2t よって 0を原点とすると OP=OQ+QP introst ( = 16 sin²³-t 2 dt の公式を利用。 (2cost2sint)+(cos(2t), sin(-2t))ヶ =(2cost+cos2t, 2sint-sin2t) (2) x(t)=-2sint-2sin2t, y' (t)=2cost-2cos2t から {x' (t)}²+{y'(t)}²=4(sin²t+2 sintsin2t+sin²2t)=1 +4(cos²t-2 cost cos 2t+ cos²2t) =4(2-2cos3t)=8 (1-cos3t) よって、求める曲線の長さは 3 3 St / 16sin222tdt = S." asin 2/2 tdt 10 大 0905 YA 3 C D St 3 = =4・ -4. [-cos/211³-¹6) ・COS ・土 3 2 0 $3+$1 Q 3t 0≤t≤ 2012/2πであるから sin ²01² 3 T(3cost, 3sint) (0²2) 5 (1) ²2=(²²+²²= < sin20+ cos20=1, costcos 2t-sintsin2t =cos(t+2t) 半角の公式により -2t3 AX T 2004: 点Pの描く曲線はハイポ サイクロイドである(p.137 でα=3、b=1の場合)。 1-cos 3t =sin²t 2 RCK TO 100 4467 ◄S³* √ {x' (t)}²³+ {y'(t)}² dt 練習 a>0とする。 長さ2maのひもが一方の端を半径aの円周上の点Aに固定して, ©287 その円に巻きつけてある。このひもを引っ張りながら円からはずしていくとき, ひもの他方の端 P が描く曲線の長さを求めよ。 8章 41 曲線の長さ、速度と道のり 下移動

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English Senior High

これの100字要約日本語でしていただけませんか?

5 19 A concerted drive to reduce obesity in one Australian town resulted in a whole generation of slimmer, faster, and healthier children, researchers reported yesterday. They said that the program, a simple mixture of persuasion and (A)incentives, was astonishingly successful. It led to 2,000 children gaining less weight, watching far less television, taze (and playing more sports. The "Be Active, Eat Well" project, conducted by Deakin University in the small town of Colac, 150 km southwest of Melbourne, ended with Colac's children weighing an average of one kilogram less than the norm for Australian children of their age. Their waistlines were an ウェスト average of cm smaller - 2 cm for boys and 4 cm for girls. Professor Boyd Swinburn from Deakin University in Melbourne said yesterday that the Colac experiment had proved to be "astonishingly successful." It was the first such program in the world to report significant reductions in waistline and weight. Professor Swinburn said: "Most people would think individual weight loss of one kilogram is not much, but here we're talking about shifting the weight of a couple of thousand kids, and 15 that's actually quite (B) phenomenal. In fact, across a population, that is absolutely huge." The experiment began three years ago when the university researchers descended on Colac's population of about 10,000 people, urging parents, teachers, doctors, and local fast-food outlets to support changes for all children aged between 4 and 12. The program included opening up more after-school activity centers for children and introducing 20 brightly colored lunch packs that contained a pitta salad wrap*¹ and fruit tub2. Parents were encouraged to (c) monitor strictly the amount of time their children watched television or walk or cycle to They were asked to encourage their children spent on computers. (3) school rather than drive them. While the researchers had hoped to cut television viewing by 10 percent, the final results 25 reported children's television viewing had dropped by 21 percent and soft drink consumption by 70 percent. There was an increase of almost 70 percent in the number of children participating in after-school sports. 10 7. ★★★ 参照チェックノート p.38 414 words 56 早稲田大学 Even the town's fish and chip shop owner switched from using animal fats to sunflower oil. He reduced the saturated fats3 in chips from 49 percent to 9.1 percent. The other fast-food outlets 30 also switched from animal fats, leading to a cut in saturated fats consumed in the town of 55 kg a week. Adults then began to follow their children's example, and the local self-defense academy went from 16 members to 75. pitta satu 1 (A (

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English Senior High

合っているかどなたか見て頂きたいです

主格の関係代名詞 ■主格の関係代名詞には who, which, that があり、後にくる動詞の主語の働きをする. 1 who 先行詞が 「人」 の場合に用いられる. ② which: 先行詞が 「物」 の場合に用いられる. 3 that NOTE 先行詞が 「物」 の場合にも「人」 の場合にも用いられる. A 次の( から適切な関係代名詞を選びなさい. 1. I want to live in a house (which/ who) has a garden. 2. Ken is a writer (which/ who) has written interesting essays. 3. I have a watch (that/who) was made in Italy. 4. I have a girlfriend (which/ that) is the same age as I am. 5. The boy (which/who) is running on the ground is my brother. 6. The shop (which/who) sells that delicious bread is closed today. 7. This is the man (which/who) wants to work at this office. 8. The girl (which/ that) runs the fastest in our school is Kanako. 9. I can't find the key (which / who) opens this door. 10. That is the doctor (which/who) lives in this village. B 次の2つの文を関係代名詞 who か which のいずれかを使って1つの文にしなさい. 11. He has a daughter. She is a teacher. He has a daughter who is a teacher 12. The man was Japanese. He took a gold medal in the Olympics. The man who took a gold medal in the Olympics. 13. This is a computer. It can receive TV. This is a computer 14. The river is beautiful. It runs through this city. The river 15. The boy is Tom. He got the first prize. The boy who which can receive TV. which runs throught this city is beautiful. got the first prize is Tom. 16. I have a friend. She lives in Korea. I have a friend who lives in 17. He is driving a car. It was made in America. He is driving a car 18. I saw a cat. It has gold eyes. I saw a cat 19. I know a woman. She can speak three languages. I know a woman in Korea. which was made in America. which has gold eyes.. 20 2 who can speak three languages. 2 F

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English Junior High

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

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