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数学 高校生

151. θはどこの角?と思ったのですがどこからこの場所(3.の解答の図の場所)であると分かるのですか?

236 43 030000 基本例題 151/3倍角の公式の利用 半径1の円に内接する正五角形 ABCDEの1辺の長さをαとし,0=2. 080057 (1) 等式 sin 30+ sin20 0 が成り立つことを証明せよ。 (2) cose の値を求めよ。 り (3) αの値を求めよ。 (4) 線分ACの長さを求めよ。 時間 最 p.233 基本事項 指針▷ (1) 30+20=2πであることに着目。なお, 0 を度数法で表すと 72°である。 (2) (1) の等式を2倍角・3倍角の公式を用いて変形すると (1) は (2) のヒント {0} COSOの2次方程式を導くことができる。 0<cos0 <1に注意して, その方程式を解く (3), (4) 余弦定理を利用する。 (4) では, (2) の方程式も利用するとよい。 解答 (1) 0から 50=2π このとき したがって (2) (1) の等式から sin 0 0 であるから, 両辺を sin0で割って 3-4sin20+2cos0= 0 3-4 (1-cos20) +2cos0=0 4cos20+2cos0-1=0 The ゆえに 整理して sin30=sin(2π-20)=-sin20 sin 30+sin 20=0 よって 3 sin 0-4 sin³ 0+2 sin 0 cos 0=0 0 <cos0 <1であるから (3) 円の中心を0とすると, △OAB において,余弦定理により AB²=OA²+OB²-20A OB cos 05(1-02005){( AC > 0 であるから AC= cos 0=1+√5 4 =12+12-2・1・1・ -1+√5-5-√5 4 a>0 であるから a=AB= (4) △OAC において, 余弦定理により AC2=OA2+OC2-20A・OC cos 20 30=2π-2050=30+20 5-√5 2 +2. −1+ 4 (*) =12+12-2・1・1・cos20=2-2(2cos20-1) =4-4cos20=4-(1-2cost)=3+2cos 2 -1+√5 (2) の(*)から。 5+√5 V 2 練習 11 ) 0=18° のとき, sin20 = cos30 が成り立つ 3倍角の公式 sin30=3sin0-4sin't 忘れたら, 30=28+0とし て, 加法定理と2倍角の 式から導く。 (3) BA (4) B C C 2751 a 1 1 0 D め ※加注 でに (1) 0=36°のとき, sin30= sin20 が成り立つことを示し, COS 36°の値を求め ある 次 sin co:

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英語 高校生

過去問の全15問の解説を宜しければして頂きたいです!!お願い致します。

3 3 [] [] ーロコ 2023 推薦 公募制推薦入試A・B 【適性検査】 文系学部 公募制推薦入試 A・B 文系学部 Ⅰ 次の英文の 選びなさい。 (1) This cheese is made ( a. about b. from c. one d. to b. between c. by d. of (2) Sally is very good () teaching tennis: she is one of the best coaches in the tennis school (3)( a. Economics b. Education C History d. Politics (4) English is a ( it. a. careless b. major c. partial d. regional ) is the area of study that is concerned with teaching and learning. (9) My father ( swimming instead. a. ought to b. should c. used to d. will a 内に入れるのにもっとも適当なものをa~dの中から1つ so as b so that C such as d. such that 00) Nowadays, millions of robots are used in various fields ( manufacture and the health industry b. in case goat's milk. n からできている C unless d. whether ) international language: people around the world speak 01) Daniel could not dance, but he pretended ( lessons. -1- ) play baseball when he was young. Now, he enjoys a, almost nothing b. as far as I know c. quite wrong d. what is called 12 Student A: Do you think you can use dictionaries in Ms. Benson's exam? ). I intend use this one. Student B: Yes, ( ) car -3- ) he had taken dance 推 (5) According to recent research, female elephants ( in the family. a. care b c. play d. sing (6) This airline allows their passengers ( them. a. of taking on b. take on c. taken on d. to take on 推 nurse (7) The sign says that () from here, that rock looks like a lion. a saw b. see C seeing d. seen (13) a. however b. wherever c. whichever d. whoever (8) Here are two different kinds of cake. You can choose ( want. I'll have the other. Mr. Tanaka ( a. Bye, for now. b. How do you do? c. It's been nice talking with you. d. What do you do? -21 00 A: I like Japanese culture. (15) ) two pieces of baggage with Ms. Davis: Excuse me. Are you Mr. Tanaka? I'm Annabel Davis. Nice to meet you. ) an important ) I'm glad to meet you. B:( ) I think Kabuki is wonderful. a. I am, too. b. Neither do I. c. So do L d. That's unlikely. c. one d. too Server: Would you like coffee or tea? Customer Actually, I'd like ( a both b, either ) one you ). Tea with my meal and coffee after

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英語 高校生

この問題解答してくださると助かります。よろしくお願いします。

V. 次の 36 36 37 1 - 38 39 40 2 3 4 3 4 2 3 4 2 3 4 40 の各組の英文の中で, 下線部に間違いがあるものを,それぞれ の中から一つずつ選びなさい。 The economist mentioned the necessity of reducing taxes. He once suffered a heavy loss on the stock market. We can't hope a quick economic recovery from the global recession. I'm searching all the folders on this computer for the missing file. The substance is said to have an anti-aging effect. There is a large difference in quality between the two products. Investors have a deep interest in the growing IT company. The typhoon has caused a great damage to the Kanto region. I didn't know our schedule had canceled until you told me so. I'd be at home having dinner now if I had caught the 6:00 train. Cindy moved to Los Angeles after she had graduated from college. Ron had been with the company for five years when he decided to change jobs. Dioxin is known to cause cancer in animals. The boy is being trained to be a pro tennis player by his father. She never imagined her husband to have such a serious disease. She invited her mother to stay with her while her husband was out of town. The new tax system was criticized for being too complicated. 2 The doctor felt his leg for checking if the bone was broken. This is a popular drug used for treating high blood pressure. I envy him for having many chances to travel abroad on business.

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