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TOEIC・英語 大学生・専門学校生・社会人

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5 A Matter of Taste Reading Passage 042 At the age of just 22, Jamie Oliver became well known across the UK as "The Naked Chef." He called himself this not because he cooked wearing no clothes, but because he wanted to simplify food preparation so that everybody could follow his recipes. He wanted to "strip down" the idea of cooking. Since then he has had numerous TV shows, published 50 many books, and has become a household name in the UK. Today, one of the activities Jamie Oliver is best known for is his great effort to improve the school dinners that children eat every day. One day, he visited the kitchen of a typical London secondary school, and he was shocked to see how much processed junk food the kids were given to eat each day. Fat and sugar levels were extremely high, and nutritional values very 10 low. The "turkey twizzler" became the symbol of these unhealthy meals: processed meat containing 21.2% fat and only 34% actual turkey. Oliver ran the school kitchen for one year and tried to show that it was possible to serve healthy meals on a limited budget—and that kids actually enjoyed eating them. His mission was to radically change the eating habits of children in that school, and across the country. 150 200 15 20 25 CULTIES 250 His project (the "Feed Me Better" campaign) has had some influence on school dinners in the UK. After watching the documentary Jamie's School Dinners, 271,677 people signed a petition calling for healthier school meals. This led the Prime Minister to agree to spend 280 million pounds (about 37 billion yen) on school dinners, to ban some junk food from school menus, and to create a School Food Trust to provide support and advice for people preparing school meals. Research, by the way, shows that children who stop eating sugary, fatty food and instead eat Oliver's school dinners are better behaved in class, and they get higher test 300 scores, too. 350 Of course, the project has had some problems. At first, many students (and even parents) resisted the removal of the junk food they were so used to. In one famous instance, some parents were passing local takeaway food to their children through the school fence. Also, schools that followed the plan for a while were often found to gradually drift back into bad habits. After all, it is easier and cheaper to just give the kids junk food. However, Oliver's efforts represent a positive start, and with obesity becoming such a huge problem (see Unit 4), 400 it's a very necessary start.

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数学 高校生

(3)の解説の意味がわからないです。 なぜy軸の負の部分と交わるとCが負になるのでしょうか。

2次関数y=ax2+bx+c のグラフが右の図で与えら34 れているとき,次の値の符号を調べよ。 (2) 6 (3) c (5) a-b+c (1) a (4) 62-4ac CHART & THINKING グラフから情報を読み取る 式の値は直接求めることができない。 「上に凸か,下に凸か」, 「軸や頂点の位置」, 「y軸との交点の位置」 などに着目して、 式の値の符号を調べよう。 解答 ax2+bx+c=ax+ = a√x + 2 b 2a 6²-4ac 4a よって, 放物線y=ax2+bx+c の軸は直線x=- 頂点のy座標は る。 6²-4ac 4a また, x=-1のとき (1) グラフは上に凸の放物線であるから 上に凸か、 下に凸か?」 (2) 軸がx<0 の部分にあるから DEGRE (1) より, a<0であるから (3) グラフがy軸の負の部分と交わるから (4) 頂点のy座標が正であるから (1) より, a<0であるから b 軸の 位置は? 2a a<0 Dy SISTAL -<0する 6²-4ac 4a b 2a' y軸との交点のy座標はcであ=d{(x+2/06)-(2/2)+c 2a b<0 a c<0 Solo's. TUTE -(b²-4ac) <0 すなわち (5) a-b+c は、x=-1 におけるyの値である。 グラフから,x=1のとき y>0 すなわち a-b+c>0 p.91 基本事項 4 基本 51 10 T FUX CARAC 62-4ac > 0 SATRASO $ax²+bx+c je z = a x 2a y=a(-1)+b(-1)+c=a-b+c =a(x+2/4)- 6²-4ac al 4a b =ax2+ (= a (x²+x)+c-1953) 7 頂点のy座標は? x=-1 における 座標は? x 軸との交点の 位置は? ↓ x a b 2a b 2a 12 -a 62 +c AJUSTE ->0) 放物線y=ax²+bx+c について, x軸と異なる2点で交 わる ⇔ b2-4ac>0 が成り立つ (p.139 以降 を参照)。 31 関数とクラン

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