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英語 高校生

訳と構文が分かんないです 1の③です

(24) 困シせん へに飛かい… him to dress like a doctor or lawyer, but he always dressed like my What my father wore embarrassed me as a young man. I wanted *I をさせる father. He wore old jeans and snapped shirts. I blamed the way he dressed for my social failures. I felt that girls 5 laughed at me because they' d seen him mowing" the grass in cut-offs" and black boots. I asked him what even at age fourteen struck me as cruel and wrong. “Why," I asked, "don' t you dress 'nice," like my friends' fathers?" He held me with his sad, shocked eyes and searched 2. for an answer. Then he said, "I like my clothes." An hour later my mother stormed into my room, slapped* me hard OT across the face and called me an “ungrateful little fool." ①In time they forgave me, and as I matured I realized that girls avoided me not because of my father but because of his son. ②I realized that my mother had slapped me because my father could not, and it soon 15 became clear that what he had really said that night was that there are things more important than clothes. He' d said he couldn' tspend even five cents on himself because there were things I wanted. Without another word, my father said, "You' re my son, and I make sacrifices so that your life will be better than mine." For my high-schoo! graduation, my father arrived in a suit. 0% Somehow he seemed taller, more handsome and impressive. It wasn' t the suit, of course, but theman. I didn' t see it again until his funeral. On the morning of his funeral, I took the suit out of his closet and changed into it. I gathered up the courage to study myself in his 25 mirror, where I appeared small and insignificant. ③AndI stood there for some time, facing myself in my father' s mirror, weeping and trying to imagine- my father' s clothes. (注)mow 草を機械で刈る slap 平手でたたく grow into (H14. 3) cut-offs ひざ上で切ったジーンズ -as I will for the rest of my life the day IlI -47-

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数学 高校生

なぜ、部分和を使わないで、2枚目のようにシグマを使って解くとダメなのですか⁇

部分和を求めて判断 基本例題 102 「次の無限級数の収束,発散について調べ, 収束すればその和を求めよ。 165 p.164 基本事項1 (2n+1)(2n+3) n=1 I+3 1 2+4 指針> 無限級数の収束,発散は部分和 S, の収束, 発散を調べる ことが基本。 Ean が収束一→ {S,} が収束 3+、5 4章 CO 2a,が発散→{S.} が発散 15 n=1 冬項の分子は一定で, 分母は積の形一各項を差の形に変形(部分分数分解)する n=1 無 ことで,部分和 S,を求められる。 級 数 (2) 各項は Tn+Vn+2 の形→分母の有理化 によって各項を 差の形に変形する。 CHART 無限級数の収束,発散 まずは部分和 S,の収束 発散を調べる 解答 第n項an までの部分和を Sn とする。 AM(分数式)のときは,部分 分数分解によって部分和を 求めることが有効。 なお,aキbのとき 1 であるから (1) an= (2n+1)(2n+3) 2n+1 2n+3 1 Sni 2n+1 2n+3 3 1 (n+a)(n+b) 1 1 2(3 2n+3 n+b b-aln+a 1 1 lim Sn 1 6 よって 2 3 ゆえに,この無限級数は収束して, その和はである。 Vn+2-/n (n+2)-n n→0 (+2-m)分·分子に n+2-n を掛ける。 _ 1 1 ニ an= Vn+/n+2 +(/n+1-nー1)+(/n+2-Vm)} 消し合う項·残る項に注意。 +1 であるから S,=(-/T)+(江-/2)+…… 1 三 四よって lim S=0 ゆえに,この無限級数は発散する。 1→0 7束すればその和を求めよ。 n

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