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数学 高校生

この問題において、赤線部のβ-αの値を具体的に求めなくても良いのはなぜですか?またそれはどの時点で判断できたら良いのでしょうか?教えていただきたいです。

(成城大) 練習 2642 曲線 y = 2x3 +3x2-12x と y = ax² (a>0) で囲まれた2つの部分の面積が等しいとき 定数αの値を定めよ。 したがって、求める の値は 曲線の共有点のx座標は 2x³+3x²-12x = ax² < 2x2+(3-α)x-12 0 の解を α, β (α <β) とすると, 解と係数の関係 2x2 + (3-a)x-12 0 の判別式をDとすると D=(3-a)² +96>0 となるから、必ず異なる 2つの実数解をもつ。 より 2x³+3x²-ax² - 12x = 0 x{2x² + (3-a)x - 12} = 0 a+B=- 3-a 2 aß = -=-12 = = -6 2 ... (2) 2曲線で囲まれる2つの部分の面 積 S1, S2 が等しいから ゆえに 1, 2 th a-3 2 {(2x³ + 3x² - 12x) = ax²}dx = ["{ax² - (2x³ + 3x² — 12x)}dx - {9(x)-f(x)}dx [{(2x³ + 3x² - 12x) = ax³}dx = [ {ax² - (2x² + 3x² −12x)}dx = 0 ◄ S" ((2x² + 3x² - 12x) = ax²}dx + √((2x³ + 3x² - 12x) = ax²}dx = 0 = " (f(x) — 9(x) dx よって y=ax² YA NY y=2x³+3x²-12x ["{(2x² + 3x² - 12x) = ax²}dx = 0 3 [ ²2 x ² + (3 − a ) ² − 6 x ² ] 3 1/2 (8-a) + ³(8³-a³)-6 (3²-a²) = 0 3 a これらを③に代入して整理すると これを満たす実数解は B₁-a² = (B-a)(B+a){(B+a)²-2aß} (B-a)(a-3) (a²-6a+105) = 0 a=3 = 0 a-3 = (B − a)- •{(²7³)² +12} 2 B²-a² = (B-a){(8 + a)² - aß} = (B-a){(ª = ³)² +6} B²-a² = (B − a)(8 + a) = (B-a). a-3 3 x 1240 [ f(x) dx + [^\f(x)dx =ff(x) dx Sa B (6+2)))) a²-6a+105 = (a-3)² +96> 0 であるから a-3=0

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英語 高校生

不定詞の問題ですが、合っているか確認して頂きたいです。

: # F 各文の( に入る最も適当な語句をa~dから選びなさい. (1) The company( the year. a. has been fired b. is being fired c. is fired (2) He was lost in the forest. To make matters ( 1 ) another 100 employees by the end of (1) p. 189 【近畿大] rain. Din a. bad 7511 a. to be disappeared ⓒ to have been disappeared d. is to fire ), it began to 【関西学院大 】 b. badly ⓒ worse d. fail (3) She went swimming, although her father told her ( a. don't do (5). not to d. to not c. not do it (4) According to the history book, the ancient city is said (a) (4) p.180 wants in a day in 500 A.D. 【武庫川女子大】 500 A.D. 「紀元500年」 b. to disappear d. to have disappeared 2 日本文の意味に合うように [ ]内の語を並べかえなさい. (1) 君の質問はこの議題とほとんど関係がない. Your question [ subject, little, this, with, has, do, to ]. Your question has little to do with this subject (2) 彼か彼女のどちらかに, そのことに責任がある。 Either he or she [to, for, blame, is, it ]. to Either he or she is blame for it. 【日本大】 (3) つまらないミスをしないようにスペルチェッカーを使いなさい. Use the spellchecker [ silly, to, make, not, as, mistakes, so ]. Use the spellchecker So as hot to make silly mistakes 【名城大 4 日本文を英文に直しなさい. (1) 君はそのバスをここで待っていさえすればいいんですよ. You have_only to wait for the bus here (2) 率直に言うと、 私は野球に興味がない. Flankly speaking, I am not interested in 各文の下線部の誤りを1か所選び 正しい形に直しなさい. (1) For young children, this kind of book could be too difficult 【関西外国語大】 to read it. [d] → (toread ) (2) The teachers were sure that John was enough smart to go to medical school. 【明海大】 [C]→(100 【追手門学院大】 (2) baseball. p.188 (3) p.192 発展 21 (1) p.194 発展 (2) p.195 発展 (3) p.185 3; (1) p.185, p.18 Typical Mistal (2) p.186 (1) p.194 発展 (2) p.188 6 不定

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英語 高校生

分かんなくてずっと悩んでます🥲 解答分かる方教えて下さい

まとめの章 1 次の各組の文がほぼ同じ内容を表すように, (1) That's the store. I bought my jogging shoes there. That's the store I bought my jogging shoes. (2) Let me do that immediately, or you will be in big trouble. Unless (6) (7) (3) He was driving the truck loaded with peaches. He was driving the truck (4) We ran away when we saw the monster. We ran away at I believe that this is the best plan possible. (5) I believe this We are sure of her satisfaction. We are sure she He admitted his guilt. He admitted that STEP 2 (9) に適切な語を入れなさい。 (11) was He regrets that he didn't work harder when young. (8) 1. He regrets (12) 〈 福島大改〉 me do that immediately, you will be in big trouble. 118 loaded with peaches. the monster. the best plan possible. to say, the rice crop in this area depends on the weather in August. Whenever I see the photograph, I remember my happy days in Scotland. (**) I never see the photograph (10) thinking of my happy days in Scotland. 〈城西大〉 worked harder when young. It goes without saying that the rice crop in this area depends on the weather in August. The student was so kind that he showed me how to get to the library. The student was kind 2 次の各文の下線部を節に書きかえなさい。 (1) He didn't expect her to finish her lesson so soon. He didn't expect (2) There can be no doubt of his being the best man for the position. There can be no doubt to show me how to get to the library. Recent pressure at work may be why he behaves in such a way. (**) Recent pressure at work may 4. for his behavior. (3) He was the first person to build a hotel in that area. He was the first person (4) People living in a big city don't know the pleasure of the country. People (5) You should be careful in crossing the road. You should be careful don't know the pleasure of the country.

解決済み 回答数: 1