1. Cho tam giác ABC, M là trung điểm của BC. Trên tia đối của tia MA lấy điểm E sao cho ME=MA a) Chứng minh rằng AC//BE b) Gọi I là một điểm trên EB sao cho AI=EK. Chứng minh I,M,K thằng hàng. 2. Cho tam giác ABC, tia phân giác của góc A cắt BC tại D. Trên tia AC lấy điểm E sao cho AE=AB. a) CMR: DE=DB b) Tam giác ABC có điều kiện gì thì ΔADB= ΔADC c) Tam giác ABC có điều kiện gì thì DE vuông góc với AC ( Vẽ hình luôn ạ)

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VIẾT LẠI CÂU DZÙM MÌN ZỚI ***CONCESSION (EVEN) THOUGH = NEVERTHELESS ALL THE SAME __Examples: They were boring, (even) though well-educated. Though they were well-educated, they were boring. Educated though they were, they were very boring. They were well-educated. Nevertheless they were boring. They were well-educated. All the same they were boring. Exercise1: 1. He didn’t tell me why he’d been late, but I knew it all the same.  He didn’t tell me why he’d been late, but I knew it ..................................................... 2. It’s rather cold, but I think I’ll go for a walk.  Even though ....................................................................... 3. She was unattractive but still had many friends.  Even though ........................................................................................ 4. She was unattractive but still had many friends.  Unattractive....................................................................... 5. Though they’d lived in London for years, they always spoke German.  They’d lived in London for years ****CONCESSION MAY… BUT = I ADMIT THAT… I GRAND THAT …...................... I CONCEDE THAT….................................. =) Note: Grant and concede are rarely used in current English. __Examples: He may have been brought up in Poland, but he has a perfect English accent. I admit that he was brought up in Poland, but he has a perfect English accent. I grant that he was brought up in Poland, but he has a perfect English accent. I concede that he was brought up in Poland, but he has a perfect English accent. Exercise 2: 1. Although he was brought up in Poland, he has a perfect English accent.  He may ............................................................................ 2. Although she’s a girl, she plays football as well as any boy.  She may ........................................................................... 3. Although she’s very rich, she never gives a penny to the poor.  She may ........................................................................................ 4. Although my sister’s very intelligent and pretty, she doesn’t have a boyfriend.  I concede ................................................................................. 5. Although he sometimes behaves like a fool, he’s really very intelligent.  I grand ...............................................................