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数学 高校生

高校数学です(F-115) 答えと私の答えの符号の向きが違っててどこが間違ってるのかがわかりません。 解説では両辺に−1をかけて符号の向きを逆にしているのですが、私はせずにそのまま計算しました。それだと答えが合わないのでしょうか。 どなたかよろしくお願いします🙇‍♀️

例題 115 三角不等式(2) *** 08.08=6 0°0≦180°のとき, 次の不等式を解け. 例 1 2cos2d-cose<0 8cos' <3+6sin 考え方 (1) coset とおくとtの2次不等式である. 0°≤0≤180° T -1≤cos 0≤1 (2)sin'+cos'0=1 を用いて sin だけの2次不等式にする. 0° 180°では 001 に注意する. 解答 (1) 2cos2-cos0<0 ......① Cost とおくと,0°180°より, t1....... ② にして E おき換えると > abo また,①は, 212-t<0 t(2t-1) <0 [等式 08120 より, o<t<1/1/...③ 3 y4 したがって, ② ③から, 20<cose< 60°1 nst (8) ③②を満たして る. よって、0°0≦180°では, 60°<< 90° 右の図より, -1 0 x x= 2 (2) 8cos' <3+6sin より, 8(1-sin20)<3+6sin0 8sin20+6sin0-5>0 (4sin0+5)(2sin0-1)>0 ここで, 4sin0 +5>0より, 2sin0-1>0 YA 1 sincos^0=1 利用 慣れたら,おき様 ないで因数分 きるようになる。 5-10 -1--1 したがって, sin0 > 2 150° 30° よって, 0°≧≦180°では, 右の図より, 30°< 6 < 150° 0 1 X sin 0≧0より、 C) MIN4sin0+5>0 Focus 三角方程式・不等式 sin, cos の種類を統一する 180°では, 0≦sin0≦1, -1≦cos01 0° tan 0 はすべての実数値 (tan 90° は定義されない)VON

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英語 高校生

①に何が入るか教えてください!! 2枚目の写真が選択肢です!

13 12 Reading 12-14 本文:米/LQ:米 Read the passage and answer the questions. Mr. Kunihiko Murai is a farmer who ( 1 ) rich from hydroponic farming. When he was young, Mr. Murai thought that the traditional way of farming was not exciting at all and he was looking for a new kind of farming. He read many books, and 5 finally learned about hydroponic farming in 1966. At first, Mr. Murai made an area to put water. He didn't add any soil, because he knew that the minerals in the water could help his plants grow. So, he put one hundred tomato plants into it. They grew fast and covered a large area. They also tasted 10 delicious. From the next year, he made the area with water bigger because he wanted to try to find the best way to grow vegetables with hydroponic farming. He used a lot of water for his experiments, so some people near his farm thought he was a very bad farmer. Later, however, more and more farmers began to 15 ask him how to do hydroponic farming because they found that 2 it was a better way. Hydroponic farming is a clean way of farming. Moreover, vegetables grow faster than the 3 ones in the fields, so farmers can grow them more often and they can get more money. Now, a lot of farmers are using this way of farming to grow their vegetables. QHints hydroponic farming [hàidrǝpánik]### area [éǝriǝ], 40 taste [téist] 〜な味がする (222 words)

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