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英語 中学生

写真の問題より、(3 )に入る言葉の模範解答がbigger,largerだったのですが私はmoreとかきました。moreだとバツにたりますかね?

Tony: What are you going to make a presentation about? Riku I'm going to introduce my idea for a new park. Here is a graph showing "Roles which people want for parks." I think parks serve many important roles. I want to make a wonderful new park in my town in the future. Tony: Great! Riku What is the most important role for parks for you? Tony: Well, I think "A place for eating" is the most important. Riku: I think that is important too. But its percentage is the lowest in this graph. Roles which people want for parks A hub for the community A place for exercise and sports A place for children to play A place for relaxing A place for eating 0% 10% 20% 30% 40% Tony Interesting. In my country, I often enjoy eating lunch in a park. Riku: I think "A place for children to play" is the most important. Many other people also want that role. Tony Yes. Its percentage is a little lower than that of "A place for exercise and sports" and "A hub for the community." But it's higher than the percentage for the other roles. Riku Parks can play a lot of roles in a town. I'll try to make a park that serves important roles. There are many possible roles for a park in a town. I hope people find good roles for my park. Tony: Great! I think your presentation will be really interesting. I want to know more about parks and towns. hub +0 <要約文> Riku is going to introduce his idea. He and Tony look at a graph that shows some (1) which people want for parks. As for the (2) important role for parks, Riku thinks it is "A place for children to play," but Tony thinks it is "A place for eating." According to the graph, the percentage of Riku's opinion is (③) than Tony's. Riku hopes to make a park that plays important roles.

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数学 高校生

次の問題で青線までは分かったのですがそこからどの様にして図示するかがよく分からないのですがどなたか解説お願いします🙇‍♂️

点P(a, b) から曲線 C:y=x-3x に接線が3本引けるとき,P(a, b) の 存在範囲を図示せよ。 点P (α, b) の存在範囲 思考プロセス a -α ともの関係式を導き、 b>g(a) 横軸を α,縦軸を6とする座標平面に領域を図示する。 既知の問題に帰着 αとの関係式を導く考え方は例題 230 と同様である。 b=g(a) 《ReAction 接線の本数は, 接点の個数を調べよ 例題 230) 解 C上の点をT (t, ピー 3t) とおく。 Jay' = 3x2-3 より, 点Tにおける接線の方程式は 209 y-(t-3t)=(3t-3)(x-t) これが点P(a, b) を通るから b-(3-3)=(3t² - 3)(a− t) すなわち 2t3-3at2 +3a+b=0 …① 950 3次関数のグラフの接線は, 1本の接線に対して接点は必 230 ず1点に定まるから, 接線が3本となるための条件はもの 方程式 ①が異なる3つの実数解をもつことである。 f(t) = 2t3-3at°+3a + b とおくと f'(t) = 6t-6at=6t(t-a) f'(t) = 0 とおくと t = 0, a x = 0, y = b を代入する。 よって, 求める条件は a = 0 かつ f(0)f(a) <0 ① f3a+b>0 ① より, (a+b) (-d+3a+b) <0 l-a°+3a+6 < 0 f(t) は極大値と極小値を もつから、f'(t) = 0 は 異なる2つの実数解をも つ。 J3a +6 < 0 よって α≠0 または 1-a+3a+b>0 すなわち ∫b>-3a \b<a³-3a fb <-3a または \b> a³-3a このときαキリであるから, 64 b=a3-3a 曲線 b = 03-3αは 点P(a, b) の存在範囲は右の図の斜 2 線部分。 ただし、 境界線は含まない。 -2- α = -1 で極大値 2 a=1で極小値 2 直線 63α は曲線 b = -3a に原点0で 接している。 b=-3a

解決済み 回答数: 1