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数学 高校生

数学が本当に苦手で分からないところがどこか分からないくらいの人です。助けてください😭😭

18 基本 例題 5 二項定理を利用する式の値 00000 次の値を求めよ。 (1) Co+nCi+nCz++nCy+....+nCn (2) Co-Ci+nCz-......+(-1)',,+……………+(-1)*, Cn (3) Co-2mCi+22C2+(-2) nCr++(-2)"nCn CHART & SOLUTION C に関する式の値 (1) p.12 基本事項 4 二項定理 (a+b)"="Coa"+nCia"-16+nCza"-262+…+nCra"-"b'+..+nCrb" の等式に適当な値を代入 二項定理と似た問題ととらえて、結果を使うことにする。 二項定理において, a=1, b=x とおいた次の等式 (1+x)"="Co+nCix+nCzx2+....+x+......+nCnxn をスタートにして、この式の右辺のxにどんな値を代入すると与えられた式になるかを考 える。 二項定理により (1+x)"=,Co+,Cix+,Cax2+...... +nCrx+......+nCnx" ① (1) 等式① に,x=1 を代入すると (1+1)=nCo+zC1・1+nCz・12+......+nCr・1' よって +....+nCz・1" nCo+nCi+nCz+••••••••••+nCn=2" (2)等式①に,x=-1 を代入すると (1-1)=nCo+nC1・(-1)+nCz・(−1)2++nCy.(-1) +....+nCz(-1)” ①の "Crx"が"Cr とな ればよいから, x=1 を 代入する。 この等式については, p.193 を参照。 ①の"Crxが(-1)'nCr となればよいから, x=-1 を代入する。 よって nCo-nCi+nCz-....... .+(-1)'nCr +......+(-1)",Cn=0 (3) 等式① に,x=-2 を代入すると +....+nCz・(-2)" (1-2)"=mCo+mC1・(-2)+nCz・(-2)2++nCr. (-2)" ←①の"Crx”が (-2) Cr となればよい から x=-2 を代入す る。 よって nCo-2nCi+22mC2+(-2)'nCr +....+(-2)"nCn=(-1)" PRACTICE 5º ConCi+mC2 2 22 2" ・+(-1)" " の値を求めよ。

解決済み 回答数: 1
英語 高校生

(1)が分からないので教えて欲しいです。

5 10 15 20 25 S1 夏期講習 第3講 宿題読解(全クラス共通) 次の英文を読んで、 設問に答えなさい。 There is an old saying in English: "Laughter is the best medicine." Until recently, few people took the saying very seriously. Now, however, (1)doctors have begun to investigate laughter and the effects it has on the human body. They have found evidence (2a)that laughter really can improve people's health. Tests were done to study the effects of laughter on the body. People watched funny films, while doctors checked their heart rate, blood pressure, breathing and muscles. It was found ). It increases that laughter has similar effects to ( 3 blood pressure, the heart rate and the rate of breathing; it also works several groups of muscles in the face, the stomach, and even the feet. beneficial. If laughter exercises the body, it must be Other tests have shown that laughter appears to be capable of ( 4 ) the effect of pain on the body. In one experiment doctors produced pain in groups of students who listened to different radio programs. The group which tolerated the pain for the longest time was the group which listened to a funny The reason why laughter can reduce pain seems to program. be that it helps to produce natural chemicals in the brain (2b)that diminish both stress and pain. There is also some evidence to suggest that laughter helps the body's immune system, that is, the system which fights infection. As a result of these discoveries, some doctors and *psychiatrists in the United States now hold laughter clinics, in which they try to improve their patients' condition by ing them to laugh. They have found that even if feel like laughing, (5)making them ilar to those 文法テキスト宿題 p69 4 問1 下線部(1)をitの内容を明らかにして日本語に訳しなさい。 問2 下線部(2a) (2b)と同じ用法の that を含む文を、次のア~オから それぞれ1つずつ選びなさい。 7. He is the man that lives next door to us. 1. It was such a wonderful movie that I saw it five times. 5. The average price of whisky is higher than that of beer. I. No one told me that he had been ill. *. The fact that she lied made him angry. 問3空所(3)に入れるのに最も適当なものを、次のア~エから1 つ選びなさい。 7. mental powers physical exercise 1. vocal exercise I. a good sleep 問4 空所(4)に入れるのに最も適当なものを、次のア~エから1 つ選びなさい。 7. increasing . reducing 1. producing I. encouraging 問5 下線部(5)を them および those の内容を明らかにして日本語に 訳しなさい。

未解決 回答数: 1