cho đường tròn (O,R) hai đường kính AB và CD vuông góc với nhau . Gọi E là điểm thuộc cung nhỏ BC ( E không trùng với B,C) tiếp tuyến của đường tròn (O,R) tại E cắt đường thẳng AB tại I.Gọi F là giao điểm của DE và AB , K là điểm thuộc đường thẳng IE sao cho KF vuông góc với AB) a) chứng minh tứ giác OKEF là tứ giác nội tiếp b)chứng minh góc OKF bằng góc ODF c)chứng minh DE nhân DF bằng 2 nhân R bình phương d)Gọi M là giao điểm của OK vafCF ,tính tan góc MDC khi góc EIB bằng 45độ

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6h2 23/5/2021 Ex1: COMBINE INTO ONE SENTENCE WITH TOO ,SO 1. They can play table tennis. We can play table tennis. They can play table tennis and we can, too (or so can we) 2. He sings love songs very well. His sister sings love songs very well. _______________________________________________________ 3. I write diary every night. My mother writes diary every night. _______________________________________________________ 4. She is swimming in the pool. Her children are swimming in the pool _______________________________________________________ 5. Hoa’ll eat bread with milk for breakfast. Hoa’s uncle will eat bread with milk for breakfast _______________________________________________________ 6. Milk is good for your health. Fruit juice is good for your health. ______________________________________________________ 7. Betty does morning exercise. Betty’s aunt does morning exercise. _______________________________________________________ 8. Lan can ski. My grandpa can ski. Ex2: Put “so” and “too” in the blanks. 1)Ali speaks French well and (my brother)......................... 2)Chris can ski( I ).................. 3)They have got a color TV, (Mary )................. 4)We live in a small flat,(they).................... 6)Tom plays chess well, (Minh)........... 9)She wears a green coat, (Bill).................. 12)Mary types well,(Lan) ............... 14)They will leave at noon,( I )............ 15)He has an early appointment,(I)............. 16)I must write them a letter,(she).............

6h2 23/5/2021 Ex1: COMBINE INTO ONE SENTENCE WITH TOO ,SO 1. They can play table tennis. We can play table tennis. They can play table tennis and we can, too (or so can we) 2. He sings love songs very well. His sister sings love songs very well. _______________________________________________________ 3. I write diary every night. My mother writes diary every night. _______________________________________________________ 4. She is swimming in the pool. Her children are swimming in the pool _______________________________________________________ 5. Hoa’ll eat bread with milk for breakfast. Hoa’s uncle will eat bread with milk for breakfast _______________________________________________________ 6. Milk is good for your health. Fruit juice is good for your health. ______________________________________________________ 7. Betty does morning exercise. Betty’s aunt does morning exercise. _______________________________________________________ 8. Lan can ski. My grandpa can ski. Ex2: Put “so” and “too” in the blanks. 1)Ali speaks French well and (my brother)......................... 2)Chris can ski( I ).................. 3)They have got a color TV, (Mary )................. 4)We live in a small flat,(they).................... 6)Tom plays chess well, (Minh)........... 9)She wears a green coat, (Bill).................. 12)Mary types well,(Lan) ............... 14)They will leave at noon,( I )............ 15)He has an early appointment,(I)............. 16)I must write them a letter,(she).............