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数学 高校生

数Aの問題です! (2)でなぜDは内分するのかを 分かりやすく教えてほしいです!! よろしくおねがいします🙇🏻‍♀️՞

直線 BC と交わる点をDとする。 線分 BD の長さを求めよ。 の二等分 (2)AB=4,BC=3,CA=2である△ABCにおいて、〈およびその外 の二等分線が直線BC と交わる点を, それぞれD, E とする。 線分DEの 長さを求めよ。 Op.361 基本事項 21 CHARY & SOLUTION 三角形の角の二等分線によってできる線分比 線分)=(三角形の2辺の比) B 内角の二等分線による線分比 外角の二等分線による線分比 → 内分 右の図で、いずれもBP:PC=AB: AC 各辺の大小関係をできるだけ正確に図にかいて考える。 解答 B A C (H+HA) (1) 点Dは辺BC を AB AC に外分するから BD: DC=AB: AC A-DATA *AB: AC=1:2 であるから BD:DC=1:2 ← AB: AC=3:6 610 HAEOL よって BD=BC=4 ←BD:DC=1:2 から →C D B BD:BC=1:1 (2)点Dは辺BC を AB: ACに内分するから CHECK ← AB: AC=4:2 BD: DC=AB: AC=2:1 または、その ゆえに DC= 1 2+1 xBC=1 この点をHとするとを また,点Eは辺BC を AB AC に外分するから BE: EC=AB: AC =2:1 ゆえに よって CE=BC=3 DE=DC+CE B DC E =1+3=4 1辺と他の 北の PRACTICE 64 (1) AB=8,BC=3,CA=6 である△ABCにおいて, ∠Aの外角の二等分線か BC と交わる点をDとする。 線分CDの長さを求めよ。 (2)△ABCにおいて, BC=5, CA=3, AB=7 とする。∠Aおよびその外角の 分線が直線 BC と交わる点をそれぞれD, E とするとき 線分 DE の長さを [(水) 椅]

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数学 高校生

黄色のマーカーの所理解できません。 教えてください🙇‍♀️

比数列の共通項 うよ。 等比数列{6} が as=b3, a=b, as≠bs 00000 重要 例題 15 等比数列と対数 373 [神戸薬大] 基本 1,9 数列{a} は初項1, 公比5の等比数列である。 a1+a2+......+α≧10100 を満 たす最小のを求めよ。 ただし, log102=0.3010 とする。 [学習院大 ] p.365 基本事項 3 基本 11 rの関係式を導く CHART & SOLUTION 1章 2 いるから, {an} の公差d,{6} の公比の関係式 対数の利用 r 三れるからrを消去するのは困難である。 まずは rとすると .pn-1 ..① 不等式の左辺を計算して整理すると 5"≧4・1010+1 このままでは,nの値を求めるのは難しい。そこで、対数(数学IIの内容)を利用するとよ い。 なお,5"≧4・10100+1 のままでは、両辺の常用対数をとって も右辺の計算がうまくできない。 そこで, nが自然数のとき 54・10100 +1と5">4・101 は同値であるから, 5410100 の両辺の常用対数をとって計算するとよい。 5">4-10100 5" 24-10100++1 4-10100 ・410100+1 等比数列の和と指数の問題 等比数列 5-1 1 = 16 ← d を消去する方針。 解答 ② から 6d=3(2-1) ③ から 6d=2(3-1) a+a2+......+an= 1-(5"-1) 5-1 =1 (5"-1) a(r"-1) Sn= r-1 ←2m²-r-1 =(r-1)(2r+1) よって,与えられた不等式から11(5-1) 10100 整理して 5" ≧4・10100+1 ゆえに,5">4・10100 を満たす最小の自然数nを求めればよ すべてのnに対して い。 an=1,6=1 両辺の常用対数をとると nlog105>10g104+100 n (1-10g102)>210g102+100 log to 2=0.3010 であるから 右辺を少なくしても 式の形からnに影響を 及ぼさない。 ←10g105"=nlog105, log104-10100 =10g104+10g1010100 =210g102+100, a=1+ (n-1)(-3). 10 0.6990n> 100.6020 10g105=10g10 2 1006090 -log. 10-19102

解決済み 回答数: 2
英語 高校生

(6)の模範解答が⭕️なのですが、問題文にはwhen Nightingale was young とあり、文中の黄色マーク🟡で引いた該当する文は、彼女が30歳になった時のことを言っているのから❌ではないのですか?教えてください🙏😭

次の英文を読んで、(1)~00までの文がその内容とあっていれば〇をそうでなければ×を解答 用紙に記入しなさい。 Florence Nightingale Florence Nightingale was born on May 12, 1920, into a wealthy family in England, and received the most luxurious education from an early age, learning not only foreign languages like French, Greek, and Italian, farmers she visited for charity work, she gradually began to think that she wanted to work in a job that but also mathematics, astronomy, psychology, and literature. However, after seeing the lives of poor served people. When she turned 30, she decided to become a nurse and started working at a hospital in London. Nightingale, who eventually became a director of a women's hospital, began to advocate the need for nurses with specialized training. At that time, nurses had a low status and were considered nothing more than servants who cared for the sick. A major turning point occurred in 1854. War began in Crimea*, present-day Ukraine, and Nightingale was sent there with 24 Catholic sisters and 14 nurses. Nightingale's efforts improved the hospital environment during the war. The Nightingale School of Nursing was established with the Nightingale Fund created during the war. Although Henri Dunant, a founding member of the International Committee of the Red Cross, highly praised her work, Nightingale was not involved in the International Committee of the Red Cross. This was because she believed that aid activities based on self-sacrifice by participants would not last long. Her famous quote, "Devotion without sacrifice is true service," expresses this well. It is said that this was due to the idea that "we rely on the spirit of service of our members, but without financial support, we are powerless." Nightingale only served wounded soldiers as a nurse for only two years during the Crimean War*, and became famous for her symbolic image of dedication and for her use of statistics to reform health care. The statistical methods she used at this time were highly praised, and she was considered a pioneer of statistics in England. Nightingale suffered from poor health from a young age, and is said to have spent most of her time in bed after returning from Crimea. Nightingale passed away peacefully at the age of 90 at her home in London on August 13, 1910. advocate* 主張する Crimea* クリミア半島 Crimean War* クリミア戦争 (1) Florence Nightingale was born in a wealthy family and she learned many foreign languages. (2) Nightingale wanted to be a nurse when she was small. P (3) It was when she was 30 years old that Nightingale wanted to be a nurse and started working at a hospital. (4) Nightingale's work in Crimea improved the environment of the hospital there. (5) Nightingale did great work to found the International Committee of the Red Cross. (6) When Nightingale was young, nurses were thought to be like servants. (7) Nightingale's famous words, "Devotion without sacrifice is true service," means self-sacrifice of the participants is always necessary rather than financial support. (8) Nightingale was not blessed with good health since young and spent much of her time in bed. (9) Nightingale is considered a pioneer of statistics in the world as she used statistics to reform health care. (10) Nightingale worked as a nurse all her life.

解決済み 回答数: 1