Tìm giá trị nhỏ nhất của bt

A= x²-3x+1

B= 9x²+x-1

trục căn thức

\(\dfrac{3}{\sqrt{3}+1}\)

\(\dfrac{2}{\sqrt{3}-1}\)

\(\dfrac{2+\sqrt{3}}{2-\sqrt{3}}\)

\(\dfrac{b}{3+\sqrt{b}}\)

Cho tam giác abc vuông tại a, đường cao ah. Biết hb=9cm hc=6cm a.tisnh ah

B. Gọi d,e là hình chiếu của h lần lượt trên ab,ac.c/m ah^2=ab.ad

tính

\(\sqrt{7-4\sqrt{3}}+\sqrt{4-2\sqrt{3}}\)

Tính:

\(\sqrt{4+2\sqrt{3}+\sqrt{13+4\sqrt{3}}}\)

giải

\(\sqrt{x^2+5x+6}\)​

\(\sqrt{2x^2+5}\)

\(\dfrac{\sqrt{x+3}}{x+2}\)

\(\dfrac{\sqrt{x^2+1}}{x-2}\)

\(\dfrac{\sqrt{x-2}}{\sqrt{x+1}}\)

Cho hình bình hành abcd ad=2ab góc a= 60 độ . M n lần lượt là trung điểm bc,ac

a. C/m am vuôg góc vs bn

b. Tứ íac bndc là hình gì

Giải pt sau X³ -7X+6=0

Add tag question to these sentences

1. Thu’s father reads a morning newspaper everyday, ___________?

2. The teacher is going to explain a new grammar lesson, ___________?

3. Their classmates were so excited about the games yesterday, ___________?

4. Lan enjoys sewing clothes for her doll, ___________?

5. Hoa did a lot of homework last night, ___________?

6. Schools may be closed if it snows heavily, ___________?

7. She has visited the citadel in Hue twice, ___________?

8. People have to rebuild the building after fire, ___________?

9. Their children enjoy playing computer games, ___________?

10. You will have a cable TV soon, ___________?

11. I am making a big mistake, ___________?

12. Let’s go shopping at Saigon Coop Mart, ___________?

13. Children should drink a lot of milk and fruit juice, __________?

14. Bring your camera with you to the party, ___________?

15. These shoes need to be fixed, ___________?

16. You must ask for your parents’ permission to join in the trip, ___________?

17. Ba likes healthy food, ___________?

18. Thu didn’t take part in the competition, ___________?

19. Phong hasn’t been to Hanoi before, ___________?

20. She can ride to school by herself, ___________?

21. My friends are used to swimming in the river, ___________?

22. His mother doesn’t work for that company, ___________?

23. They don’t have to buy new dictionaries, ___________?

24. It will rain tomorrow, ___________?

25. Remember to buy your mother some sugar on your way home, ___________?

26. She has read this news on the internet, ___________?

27. They have seen lots of Beckham’s pictures on his website, ___________?

28. You think Internet is a means of education, ___________?

29. There was a lot of traffic in the streets yesterday, ___________?

30. You ought go now, _______________?

31. I think she won^’t come to your party, _______________?

32. What a nice dress, ___________?

33. It is time for you to study hard, ______________?

34. You need go right now, _____________?

35. He need never study hard, _________________?

36. You think it is going to rain, __________________?

37. He said that his father was a doctor, _______________?

38. Everything is all right, __________________?

38. She met nobody at the party, _________________?

39. Don^’t forget to turn off the lights before going out, __________________?

40. Be careful with that man, _________________?

41. Someone had come to our room, ______________?

41. She likes nobody to help her, _______________?