学年

教科

質問の種類

数学 高校生

82. 記述に問題ないですよね??

130 0000 基本例題 82 共線条件,共点条件 (1)3点A(-2,3), B(1,2), C(3a+4, -2a+2) が一直線上にあるとき aの値を求めよ。 (2) 3直線4x+3y-24 = 0 ax+y+2=0 ...... ①, x-2y+5=0 ③が1点で交わるとき,定数aの値を求めよ。 基本 76 ...... 指針 (1) 異なる3点が一直線上にある (共線) .........! ⇔2点を通る直線上に第3の点がある 点Cが直線AB上にあると考える。よって,まず,直線 AB の方程式を求める。 (2) 異なる3直線が1点で交わる (共点) ⇔2直線の交点を第3の直線が通る ········· 7 _ 045. AD-80 DEA- 2直線①,②の交点の座標を求め,これを③に代入する。 解答 (1) 2点A,Bを通る直線の方程式は 2-3 y-3= 2-3 1-(-2) 1_(−2){x-(-2)} すなわち x+3y-7=0 直線AB上に点Cがあるための条件は 3a+4+3(-2a+2)-7=0 -3a+3=0 練習 Ⓡ82 止めよ。 ゆえに よって a=1 別解 -2=3a+4 すなわち α=-2のとき,直線AC の方程式 は,x=-2となる。 (1) 点Bは直線x=-2上にないから, αキー2である。 4'0 ▼ 「BC上にAがある」 また ための条件はのは 「AC上にBがある」 もよいが, 計算がらくにな る場合を選ぶ。 -2a+2-3 3a+4-(-2) 3a+6=3(2a+1) ゆえに よって a=1 (2) ①, ② を連立して解くと x=3, y=4 2直線 ① ② の交点の座標は (3, 4) 点 (3,4) が直線 ③ 上にあるための条件は a 3+4+2=0 よって E+ aキー2として, 3点A,B,Cが一直線上にあるとき,直線 AB の傾きと直線ACの傾きは等しいから すなわち B 直線AB上に C SAA 2, これはαキー2を満たす。 a=-2 中心 2a+1 3a+6 ○重要8 AB の傾き = AC の傾き を利用する解法。 ただし、 この考え方はx軸に垂直 な直線には通用しないから、 その吟味が必要。 なお、似た考え方をベクト ル (数学B)で学ぶ。 (1) 異なる3点 (1, 1), (3,4), (a, α²) が一直線上にあるとき,定数 (8 ■交点の座標を求める2直線 は,係数に文字を含まない ① ② を使用する。 え 重要 異な が1 指針 解答 2直線 点(3, また, 方程式 すなわ よって る。 別解 その 3直 の直 つま であ でゆら or of ゆえ

回答募集中 回答数: 0
英語 高校生

教えて下さると嬉しいです(><)

Circle the correct answer for each question. A. likely to be jealous of someone 1. You are more 2. Which do many people decorate at Christmas time? 3. Which are people more accustomed to? 4. Which of these is a weapon? 5. Which of these flows? a. rich b. poor a. a feast b. a tree a. spending money b. receiving awards b. a rifle b. water b. ruin it b. confused b. a feast b. a contract a. a recruit a. being punished b. getting a reward B. Complete the paragraph with items from the box. Two items are extra. 6. What would profit do for a business? 7. Which would people rather be? 8. Which would you invite friends to share with you? 9. Which would you sign? 10. Which would few people enjoy? discovered resembled establishing rights faced status a. an empire a. an insect a. help it a. excited a. a contract grief the rest of (9) by Roy's son and (10) heir took over Many people change countries during their life, but one man has (1) (2) himself by his own country. During World War II, the UK built a number of artificial platforms in the sea to contain (3) that would be used to fight off invaders. After the war, the soldiers left these platforms and they were forgotten - until 1967. In that year, a British man, Roy Bates, (4) one of the platforms and announced he had started his own country, called Sealand. This surprised people in the UK, who believed they had the (5) - Bates and (6) to leave the platform. However, Roy (8). made a name for weapons to the platform. orders In 1968, a court decided that the UK had no power over Sealand. Just like other places with the that the platform was in international waters. of a country, Sealand, has its own stamps, coins, and passports. It is controlled 'Prince' Michael, and is home to a large Internet business. the people on the island (his family), (7) in 11 - 15 69

回答募集中 回答数: 0
英語 高校生

教えて下さると嬉しいです(><)(><)

A. Circle the correct answer for each question. likely to be jealous of someone 1. You are more 2. Which do many people decorate at Christmas time? 3. Which are people more accustomed to? a. rich a. a feast b. a tree a. spending money b. receiving awards a. an empire b. a rifle a. an insect b. water a. help it b. ruin it a. excited b. confused a. a contract b. a feast a. a recruit b. a contract a. being punished b. getting a reward B. Complete the paragraph with items from the box. Two items are extra. 4. Which of these is a weapon? 5. Which of these flows? 6. What would profit do for a business? 7. Which would people rather be? 8. Which would you invite friends to share with you? 9. Which would you sign? 10. Which would few people enjoy? discovered resembled establishing rights called Sealand. faced status - Many people change countries during their life, but one man has (1) (2). This surprised people in the Bates and (6) to leave the platform. However, Roy (8). (9) by Roy's son and (10) grief the rest of heir took over in the sea to contain (3) that would be used to fight off invaders. After the war, the soldiers left these platforms and they were forgotten - until 1967. In that year, a British man, Roy Bates, one of the platforms and announced he had started his own country, b. poor himself by his own country. During World War II, the UK built a number of artificial platforms made a name for weapons who believed they had the (5) the people on the island (his family), (7) to the platform. orders In 1968, a court decided that the UK had no power over Sealand. Just like other places with the that the platform was in international waters. of a country, Sealand, has its own stamps, coins, and passports. It is controlled 'Prince' Michael, and is home to a large Internet business. in 11-15

回答募集中 回答数: 0
英語 高校生

教えて下さると嬉しいです。。涙

Circle the correct answer for each question. A. likely to be jealous of someone 1. You are more 2. Which do many people decorate at Christmas time? 3. Which are people a. rich a. a feast a. spending money b. receiving awards a. an empire b. a rifle a. an insect b. water a. help it b. ruin it a. excited b. confused a. a contract b. a feast a. a recruit b. a contract a. being punished b. getting a reward B. Complete the paragraph with items from the box. Two items are extra. 4. Which of these is a weapon? 5. Which of these flows? more accustomed to? 6. What would profit do for a business? 7. Which would people rather be? 8. Which would 9. Which would you sign? 10. Which would few people enjoy? discovered resembled you invite friends to share with you? called Sealand. establishing rights faced status grief the rest of Many people change countries during their life, but one man has (1) (2) heir took over (9) by Roy's son and (10) This surprised people in the UK, who believed they had the (5) . Bates and (6) to leave the platform. However, Roy (8) - b. poor in the sea to contain (3) that would be used to fight off invaders. After the war, the soldiers left these platforms and they were forgotten - until 1967. In that year, a British man, Roy Bates, one of the platforms and announced he had started his own country, b. a tree himself by his own country. During World War II, the UK built a number of artificial platforms the people on the island (his family), (7) - - made a name for weapons to the platform. orders In 1968, a court decided that the UK had no power over Sealand. Just like other places with the that the platform was in international waters. of a country, Sealand, has its own stamps, coins, and passports. It is controlled 'Prince' Michael, and is home to a large Internet business. im 11 - 15

回答募集中 回答数: 0