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数学 高校生

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確率変数の期待値,分散,標準偏差 発展例題 12400 基礎 例題 105 から6までの番号をつけてある6枚のカードがある。 この中から2枚のカ コードを同時に引くとき, 引いたカードの番号の大きい方をXとする。 この とき、次のものを求めよ。 (1) Xの期待値 CHARI & GUIDE 確率変数 X の期待値,分散,標準偏差 E(X)=2xp. V(X)=E(X²)—{E(X)}², 0(X)=√V(X) まず、Xのとりうる値を求める。 X=1 はあり得ないから、Xの確率分布(X=2, 3. 4,5,6) を求める。なお, 番号 Xは整数であるが, 期待値や分散は整数になるとは 限らない。 1 E(X)=2+3+4+ 15 解答 6枚のカードから2枚を引く方法は全部で C2 = 15 (通り) (1)X=k(kは整数で2≦k≦6) のとき, 1枚は番号がんのカー ドで残りは (k-1) 枚 から1枚選ぶから Xの 確率分布は右の表のよう になる。 よって, Xの期待値は 15 (2) (1) から Xの分散は V(X)=E(X)-(E(X))^ -70 196 14 9 3 9 (3) (2) から Xの標準偏差は a(X)=√V(X)=₁ (2) Xの分散 EX 105 V 9 X P - √14 3 2 3 1 15 456 15 2 (3) Xの標準偏差 4315 +6· 5 6 計 15 15 15 15 || - (2²-½ + 3³²- ²/5 + 4²² ³35 +5² +53 +6²-)-(¹) 2 +3².. 4 15 15 15 15 4 5 5 70 14 15 15 3 1 (2) V(X)=E((X-m)) で求めると、次のように 計算が大変になる。 v(x)=(2-1)³.5 +(3-14). /1/2 COLT +(5-1) ²1/1 · (64+50+12 135 +4+80) 210 14 =1/4 135 率定数aX+bの期待値, 分散 例 106 例題 X を確率変数, a, bを定数とする。 Xの分散 V (X) と αX + b の分散 ▲発展例題 123① (X+6) においてV(aX+b)=²V (X) が成り立つことを証明せよ。 (②) 赤玉3個と白玉2個の入った袋から, 3個の玉を同時に取り出すとき, 3 のうちの赤玉の個数をXとする。 このとき, 確率変数 2X +3 の期待値 と分散を求めよ。 2個のさいころを同時に投げるとき 出た目の小さい方をXとする。 こ the CHART 確率変数aX+bの期待値,分散 E(aX+b)=aE(X)+b, V(aX+b)=a²V(X) (1) E(X)=m とすると 分散の定義F(X)=E((X-m)") を利用。 (2) まず, Xの確率分布を求め, E(X) と V(X)を計算する。 GUIDE E(X)=mとすると E(ax+b)=aE(X)+b=am+b よって V(ax+b)=E({(ax+b)(am+b)}}) = E((aX-am)²)=E(a²(X-m)²¹) =a²E((X-m)²) =a²V(X) E(aX+b)=am+b Xのとりうる値は 1 2 3 である。 CX2C23 P(X=1)= = 5C3 10 3C3 1 5C3 10 P(X=2)=3C2X2C1 6 P(X=3)= よって,Xの確率分布は右の表の ようになる。 ELX)=1+30 +2.00 +3-10-18 - 23/0 6 9 +3・ 10 5 X 1 2 3 計 3 6 1 P 10 10 10 ゆえに 一致しないけど、(2x+3)=2F(X)+5=2 5 どこが間違ってますかそx)=4. 9 25 SC3 9 18 v(x)= (1²• 10 V(X)-(1³.36 +2³.5+3². 1)-(2)²-½-( ? ) - ² 6 10 36 25 1 33 -V(X)=E((X-m (変数)(確率 7 v(x)=E√(x-m³²² aE 本当にそうなるか知りたい から105の問題の数を 代入したら. -V(X)=E(X¹3(EX) 4章 x=3のとき V(3)-143-447 488 orq 20 14(2714) 44.43 -V(2XV +3" とるな 確率変数の期待値と分散

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英語 高校生

(3)について答えはthese new types of cementまたはnew types of cement ですがthe new types of cement でも大丈夫ですか?

6 2019年度 英語 Ordinary Portland cement-t produced by baking lime in a kiln and emits approximately one ton of carb a kiln and emits Cement production is responsible for cement. dioxide for every ton of approximately 5% of global man-made CO2 emissions, according to the World Business Council for Sustainable Development. Cement does absorb some carbon dioxide back from the atmosphere over time, One 2016 study estimated that between 1930 and 2013, the equivalent of 43% of CO2 released from lime during heating was reabsorbed by - although that percentage does not include carbon concrete products worldwide dioxide emitted by the fossil fuels burned to heat kilns, a significant contributor of says. Fennell notes. 東京医科歯科大前駅 - the most common form in concrete- CO2 emissions during production. Unfortunately, this absorption comes at a price, particularly when cement is used in structures that feature steel reinforcement bars (rebar) within concrete. vl(As) CO₂ moves through cement it changes the pH of the surroundings, Fennell says. Concrete loses its alkalinity and, when moisture and oxygen are present, causes the rebar to rust. 2) ad "Rusting steel can expand with great force to as much as nine times its original dimensions if you add up all of the layers of iron oxide," says Randolph Langenbach, an international consultant in building conservation. This expansion causes the concrete to crack, flake and crumble. Svi aft ni adosband huma Degradation is a massive concern, he argues, and problems are not limited to rusting rebar. Everything from air pockets left in the concrete mix when it's laid to salt air buffeting coastal-facing walls, or the use of beach sand in the concrete, can shorten a building's lifespan. As one specialist once put it to Langenbach: "If it ain't cracked, it aint concrete."qubong ao yas guidtyns ogde stornos 90 s of fshoqml is vatns mash *** long llopsd lust ay to Given the concerns about the environmental impact and structural longevity of concrete, why do we continue to build with it? addi Simply put, concrete is cheap, versatile, quick to erect and requires no of weight J

未解決 回答数: 1
英語 高校生

至急!!私立大学看護学部の過去問です。答えがないため、回答を作って欲しいです!!科目は英語です。

プペンシルで解 people than ever can find an audience time filled with disasters, online, "conspiracy theories seem to be growing crazier by the day. We also tend to believe in such things under increased stress, which is unfortunate because many of these ideas are Some conspiracy theorists pride themselves on being "critical freethinkers," but a new damaging our democracies and ourselves. study showing a connection between lower critical thinking skills and increased conspiracy (2) theory belief suggests this may not be the case. "Conspiracy theories refer to attempts to explain the ultimate cause of an important event (social, political, climatic, etc.) by accusing a hidden group of perceived evil, powerful people or organizations of having secretly planned and carried out these events," say Paris Nanterre University psychologist Anthony Lantian and team in their paper. two studies, the researchers tested the critical thinking skills of 338 a French version of the Ennis-Weir Critical Thinking Essay Test. They then scored the students' tendencies towards conspiracy beliefs and their personal Across undergraduate students (4) the objective analysis and assessment of their own critical thinking skills. Critical thinking. evaluation of a situation requires a collection of cognitive skills. These include the ability to distinguish between relevant versus irrelevant information, think systematically, see other perspectives, recognize and avoid logical *fallacies, look beyond the obvious, be aware of and avoid biases, and change your mind in light of new evidence. "The more people believe in conspiracy theories, the worse they perform on a critical thinking ability test," Lantian said. "This test is characterized by an *open-ended format highlighting several areas of critical thinking ability in the context of argumentation." (6) All this is not to say that those with high critical thinking skills can't also be sucked into believing things that may not necessarily be true. The way (7) [is wired /a/ makes / thinking/ social species / our / as] us very vulnerable to believing those we identify with as part of our own cultural group- no matter how much education we have had that boosts science literacy. Trust plays a massive role in who we believe. We also have a tendency to believe each of us is above average at detecting misinformation, which can't possibly be true. Researchers have also linked this need to feel special to greater belief in conspiracies. Lantian and team point out that while their study suggests critical thinking lowers Deople's chances of believing in untrue conspiracy theories, the findings don't determine if (8) (9) た場合,そ 数学【数学 験番号 【化学 b てお 3 In a more (1) ① 次の英文を読んで、下の設問に答えなさい。 1 - (3) the po no a E

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英語 中学生

この問題の(4)なのですが、 I will try anything faster than any other student in my class. どんなことも他の人(クラスメート)よりも早く挑戦する と解答したのですが、あっていますか? 添削お願いします。

19 ハルナ(Haruna) がヒューズ先生 (Mr. Hughes) と話をしています。この対話文を読んで、 [1]~[(3) に入る最も適当なものをそれぞれあとのア~エのうちから一つずつ選び、その 符号を書きなさい。 また、対話文の内容に合うように、 (4) に入る言葉を英語で書きなさい。 ただし、語の数 は10語程度(.?! などの符号は語数に含まない。) とすること。 Haruna Mr. Hughes, do you have time ? Mr. Hughes Of course. Do you have any questions? Haruna:Yes, at the end of the class, you said, "Be the first penguin." (1) Mr. Hughes: All right. You know penguins, right? Penguins are birds that cannot fly but car swim in the sea. Haruna Yes, of course. I have seen them in an aquarium. Mr. Hughes : Some people say that there is no leader in the world of penguins but that is not true. When they catch food or run away to a safe place, one penguin moves first, and then the rest of them (2) Haruna Mr. Hughes: Wow, that's very interesting. For example, (3) | to jump into the sea to catch food because there is sometimes danger in the sea. But when one brave penguin jumps into the sea, all 0000/r

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