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英語 高校生

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20 Unit 1 - History - Gutenberg is famous for inventing printing, but he didn't really invent it. He invented a better way of printing. [2] For hundreds of years people used blocks of wood* to print. They used a knife to cut words backward in the block of wood. Then they covered the block with ink and pressed it onto paper. When they pulled the paper from the inky blocks, the words appeared on the 金属 5 paper in the right direction. In Korea and China, people printed with metal type* instead of 右向き wood. (2)Either way, printing was difficult and very slow. It took several years to make one copy of a book. [3] Books were very expensive and rare. Only ( 3a ) people could buy them, and ( 3b ) 10 people could not read. But, as ( 3c -) people learned to read, books became more popular. So people wanted to find a quicker, better and less expensive way to print books. One of these people was Johannes Gutenberg. opsugas.l Y tinU 9003 iinil 4 Gutenberg was born in Mainz, Germany, around 1400. He was good at working with metal, but probably had no idea how people printed in China. His idea was to make a piece Clarey operan 15 of metal type for each letter of the alphabet and use the letters (4)over and over. (5)He could put the type together to make words and arrange words to make pages. With ink on the type, he could press paper on them to print a page. A "printing press" machine could make hundreds of copies of a single page quickly. After that page, he could rearrange the same letters to make other words and print other pages. LISSH Si nou 5 It took Gutenberg a long time to make the type for each letter of the alphabet. When he finished the type, he didn't have enough money to make the printing press. He borrowed money from a man named Johann Fust. After many years, Gutenberg's printing press was Legione ready. Gutenberg printed his first book, the Bible, around 1455. 6 There are only twenty-one complete copies of the original Bible. They are some of the 25 most expensive books in the world. In 1987, part of a Gutenberg Bible sold for $5.3 million. 7 Today people remember Johannes Gutenberg. The city of Mainz has a statue of him and a museum. His original printing press is in the museum. (6)They print several pages a day to show that it is in good condition. earoviaU 012mu 394 words/#IN block of wood: type: vrigsypola 01 sind 7 an Oupside down & 下線部 (6) を日本 7. 本文の内容に合わ Many people & Gutenberg g Gutenberg Olt was a long Though Gu cost a lot of Hannes Rotest

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数学 高校生

青チャート⑴解説下から4,5行目 ①から「AHベクトル=~,BHベクトル=~」といえるのが何故なのか分かりません。もし①の条件がなくOがBC,CA上にあったらどうなるのですか? また先程の「AHベクトル=~,BHベクトル=~」がいえると「AHベクトル≠0ベクトル」「BH... 続きを読む

00000 基本例題 30 線分の垂直に関する証明 △ABCの重心をG, 外接円の中心を0とするとき,次のことを示せ。 (1) OA+OB+OCOH である点Hをとると, Hは△ABCの垂心である。 (2)(1) の点Hに対して,3点O,G,Hは一直線上にあり GH=20G Sint flyta [類 山梨大 ] 基本23 基本68 SHU 指針▷(1) 三角形の垂心とは, 三角形の各頂点から対辺またはその延長に下ろした垂線の交点で OK-ある。 BHOJE AH 0, BC ¥0, BH ¥0, CA ¥0 のとき OA上への ...... (A) AH⊥BC, BH⊥CA⇔AH・BC=0, BH・CA = 0 内積を利用して, ⑩ ((内積)=0] を計算により示す。 とは△ABCの外心であるから 10A-10 |OA|=|OB|=|OČ| も利用。 MAA CHART 線分の垂直 (内積) = 0 を利用 MOTSTAND この長さと同分 であるとい 解答 直角三角形のときは ∠C=90° とする。 (1) ∠A=90°, ∠B=90° としてよい。 このとき,外心O は辺BC, CA 上 にはない。 このとき, 外心は辺AB上 ① にある (辺ABの中点)。 OH=OA+OR+OCから 10+800) AH-OH-OA=OB+OC B A ゆえに AH・BC A (50 =(OB+OC) (OC-OB) = |COC-OB (分割) = 40A = |OC|²—|OB|²=0 0-51ABCの外心 0 → 同様にして メ5-0 BH・CA=(OA+OČ)・(OA-OC) = OẢI—|OCI=0 - -1-5-JA また①から AH=OB+OČ=0, BH=OA+OC≠0 ¥0, ときによって、AH, BC BH CAであるから AH⊥BC, BH⊥CA すなわち AH⊥BC, BH⊥CA 点Hは△ABC の垂心である。 したがって, Jos ならば OA+OB+OC=/OH から OH=30G -+* (2) OG= 3 ゆえに GH = OH-OG=2OG よって, 3点 0, G, H は一直線上にあり 10 GH=20G 428 OH-OA = OB + OC are 5+₂09 初めて、 a·b=0" いえる!!! CLO A OA=OBOC (数学A) 検討 外心,重心,垂心を通る直線 (この例題の直線 OGH) を オイラー線という。 ただし、正三角形は除く。 POSTO (1) から OA + OB+OC=OH BASA+SA

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