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数学 高校生

この問題で、解答ではAH=sAB+tACで解いてますが、✱の部分のlOA+mOB+nOCの方法で解いてくれませんか この方法でやると何故か全部0になるんですけど

基本例題69 平面に下ろした垂線 (1) 17 00000 空間において, 3点A(5, 0, 1),B(4, 2, 0), C(0, 1,5) を頂点とする三角形 ABCがある。 原点O(0, 0, 0) から平面ABCに垂線を下ろし, 平面ABCとの 交点をHとするとき, Hの座標を求めよ。 基本 67 指針 点Oから平面ABCに下ろした垂線の足に対して, 大点は平面ABC上にあり, ととらえて考える。 10×120×HAO. 直線 OH は平面ABCに垂直であるから, 直線 OH は平面 ABC 上のすべての直線と垂直である。 よって ゆえに よっては OH⊥AB, OH LAC ゆえに OH・AB=0, OH・AC=0 解答 AB=(−1, 2, −1), AČ=(−5, 1, 4)×0+0×$+(1−)×(1 点Hは平面ABC上にあるから, AH=sAB+tAC (s, t は実 数) (*) とおける。 ゆえに OH OA+AH 右上の =OA+sAB+tAC =(5,0,1)+s(-1, 2, -1)+t(-5, 1,4) ① OHLAB, OHLAČ OH」 (平面ABC) であるから OH⊥AB から OH・AB=0 よって ゆえに 2s+t=2 OHACから =(5-s-5t, 2s+t, 1-s+4t) -(5-s-5t)+2(2s+t)−(1¬s+4t)=0 s+14t=7 - PI=. ...... OH・AC=0 h=-5(5-s-5t)+1・(2s+t)+4(1-s+4t)=0 ② ③ を解いて ...... かつ,直線OHは平面ABCに垂直である S= 7 9 よって, ① から KOOTUSTE t= 9 H(2, 2, 2) ...... 4 9 mx C (8 0 I- ZA JUAN C BD HO 重要 71 CA H OH =LOA+mOB+nOC, け+m+n=1 として考えても よい。 B (HAL)=(A)+(8A)+(ADA) すものであり、 y TOATE CA 8 8 90/1 0 2) B(2 1 (0) CU C Hote FORSERORTE 3

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英語 高校生

FLEX2 レッスン3 教科書のcompressionが分からなさすぎてヘルプです

Choose the appropriate answer. hartan art ell 1. It became more important for people to get salt a. when Roman soldiers were given money to buy it b. when people started to hunt animals for food c. when people ate less meat and began to eat more grains and wheat 3. The influences of salt can be seen a. in modern cultures b. not in languages but in customs and religions c. more in languages than in customs or religions boyasdo 2. What ancient people discovered was a. that salt could stop droughts and help people survive a lack of food b. that salt helps bacteria grow foods c. that salt keeps foods from going bad 4 4. Thanks to some discoveries by scientists, a. people have changed how they produce salt b. people have begun to use salt in new ways edme c. people have found that salt has always had an influence on many cultures Salt is 1 dor d blues 2 Fill in each blank with the most appropriate word to complete the summary. EXTER Jika ODOY velg avs ) for our lives and we cannot live without it. In ancient times, as people be eat more food which were low in salt, they needed a lot more salt to survive. Eventually it bec 2 3 ) trade item. Also, salt was used to ) famines and travel to ) food. Because of this, people 5 ancient people, has also 6 ) places. Salt, which was very importa modern cultures. Some used, and its influence can also be found in some ) related to salt an 8 ). One important scie 9 ) enabled people to produce new things. Salt is now a common item, but it has had ) on the world. 10 7 affected / available / decrease / discovery distant expressions impact / precious / preserve / religions essential survive

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数学 高校生

黄色の蛍光ペンで引いている部分が分かりません。 OPベクトルは異なる2点を通っているので、直線Lの方程式はOPベクトル=(1−t)OAベクトル+tOBベクトルだと思ったのですが、なぜOPベクトル=OAベクトル+tOBベクトルとなるのですか。

A 239 空間内に3点 A (1,2,3),B(3,5,2), C (1, 2, 1) がある。 点A, B を通 る直線をeとしたとき、点Cとの距離が最小となるe上の点の座標を求めよ。 ¥240 空間ベクトル α = (2,1,-2), 6 =(3,-2, 6) に対して, c=ta +6 (tは実数) とする。 [13 早稲田大]* | | の最小値を求めよ。 がことのなす角を2等分するときのtの値を求めよ。 ☆ [09 名城大]* (2) s の値を求めよ。 S 241 四面体OABC に平面 α が OA, AB, BC, OC とそれぞれP,Q,R, S で OP: PA=AQ: QB=BR: RC=1:2 を満たすように交わっている。 d = OA,B,C=OC と OS = sc とおく。 (1) PQ, PR, PS をs, a,b,c を用いて表せ。 2 16:10 ABI-LACI²-AP 4607 [12 大阪府立大] ★242 0 を原点とする座標空間に 3点A(2,0,0), B (0, 5,0),C(0, 0, がある。 原点Oから△ABC へ垂線を下ろし、 △ABC との交点をHとする。 (1) △ABCの面積を求めよ。 (②2) OH の長さを求めよ。 B 243 四面体OABCの各辺の長さをそれぞれ AB=√7, BC=3,CA=√5, OA=2,OB=√3, OC=√7 とする。 OA=4,OB=6,OC=c とおくとき、次の 問いに答えよ。 (1) 内積 を求めよ。 (2) 三角形OAB を含む平面をαとし, 点Cから平面αに下ろした垂線とαとの交 点をHとする。このとき, OH を 言で表せ。 (3) 四面体OABCの体積を求めよ。 [13 福井大] I

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英語 高校生

この問題の答えを教えてください🙇‍♀️

【IV】 次の(A), (B)の設問に答えよ。 ((A)11点,(B)6点) (A) 次の英文を読んで、 下の設問に最も適切な解答をせよ。 選択式の設問は記号 (アイウエ・・・) を1つ選んで答えること。 A World Bank report recently released suggests climate change could, force 216 million people across six regions to migrate within their countries in the next 30 years, with ""hotspots" emerging within the next nine years ( 2 ) urgent steps are taken. ) urgent steps are taken.numputė, valab The "Groundswell Part 2" report examines how climate change is a powerful driver of migration within a nation because of its impact on people's livelihoods through droughts, rising sea levels, crop failures and other climate-related conditions. The original Groundswell climate. report was published in 2018 and detailed projections and analysis for three world regions: sub- Saharan Africa, South Asia and Latin America. "Groundswell 2" conducted similar studies on East Asia and the Pacific, North Africa, and eastern Europe and Central Asia. Both studies established different scenarios to explore potential future outcomes and identify internal climate in- and out- migration hotspots in each region that is, the areas from which people are expected to move, and the areas to which they might go. The study suggests that by 2050, sub-Saharan Africa could see as many as 86 million internal climate migrants; East Asia and the Pacific, 49 million; South Asia, 40 million; North Africa, 19 million; Latin America, 17 million; and eastern Europe and Central Asia, 5 million. To slow the factors driving climate migration and avoid these worst-case outcomes, the report recommends a series of steps world leaders can take, including reducing global emissions (4) the goals established by the Paris 2015 climate agreement, and taking steps to better understand the drivers of internal climate migration, so appropriate policies to address them can be developed. (注)* hotspot: 自然破壊が進み, 危機に瀕している地域 -2/ Which of the following has the closest meaning to", force"? to talk someone out of doing something to keep someone from doing something to tell a lie I to make someone move 2 Put the best one into blank 2. 7 unless イ 1 ア イ once when I if ウ 3 Which of the following has the closest meaning to "3 a powerful driver"? ア a good person who drives a truckgran amma di kaill) a tool to fix some furniture I 0811 a strong power that causes something to happen a condition which causes climate change 4 Put the best one into blank 4. Pin line with イ I on behalf of in spite of even though

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