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THE TRAM SYSTEM IN HA NOI: THEN AND NOW Ha Noi had its first tramways in 1900. The tram system was a major means of transport in the city for nine decades and thus the image of the tram and its clanging sounds have gone deep into the hearts and minds of Hanoians. Since it was convenient and cheap to get around the city and to the suburban areas by tram, the system was very popular. However, due to the population boom and the need for a wider road system, the last rail track was removed. Now,...
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THE TRAM SYSTEM IN HA NOI: THEN AND NOW

Ha Noi had its first tramways in 1900. The tram system was a major means of transport in the city for nine decades and thus the image of the tram and its clanging sounds have gone deep into the hearts and minds of Hanoians. Since it was convenient and cheap to get around the city and to the suburban areas by tram, the system was very popular. However, due to the population boom and the need for a wider road system, the last rail track was removed.

Now, after more than 20 years, the population of Ha Noi has risen from about two million people to more than six million people; therefore, the number of vehicles on the roads has increased dramatically. To meet the increasing travel demands, Ha Noi is launching its first skytrain system, connecting Cat Linh and Ha Dong. The system is expected to begin operations by 2016, with initial four-compartment skytrains. Furthermore, a new rail system project including around eight kilometres of skytrain rail and four kilometres of subway rail, connecting Ha Noi Central Station and Nhon, has also been under construction and is expected to be completed in a few years.

1. In which century was the tram system built?

2. What was the role of the tram system in Ha Noi?

3. When was the system removed?

4. What has happened to Ha Noi's population over the last two decades?

5. How has the tram system in Ha Noi been improved recently?

6. Which of the transport systems do you think more impressive to Hanoians?

1
28 tháng 11 2022

1. In the 20th century.

2. It was a major means of transport for Hanoians.

3. In 1990.

4. The population has increased dramatically.

5. New rail systems including a skytrain and a subway are under way.

6. I think the old train is more impressive to Hanoians because the train in Hanoi and its clanging sound have gone deep into Hanoians’ mind and heart.

28 tháng 11 2022

`x-2sqrt{x-4}=4`              `đk : x>=4`

`<=> 2sqrt{x-4} = x-4`

`<=> 2*(x-4)=(x-4)^2`

`<=> 2x-8 = x^2 -8x +16`

`<=>2x-8-x^2+8x-16 =0`

`<=> -x^2 +10x -24 =0`

`<=> x^2 -10x +25 -1 =0`

`<=> (x-5)^2 =1`

`=> [(x-5=1),(x-5=-1):} =>[(x=6(t//m)),(x=4(t//m)):}`

Vậy `S={6;4}`

29 tháng 11 2022

Đặt \(\left\{{}\begin{matrix}a=3x^2-4x+1\\b=3x^2+2x+1\end{matrix}\right.\left(a,b\ne0\right)\Rightarrow x=\dfrac{a-b}{6}\).

Phương trình đã cho trở thành

\(\dfrac{2}{a}+\dfrac{13}{b}=\dfrac{36}{a-b}\\ \overset{\text{nhân chéo và rút gọn}}{\Rightarrow}2b^2-25ab-13a^2=0\\\Leftrightarrow\left(b-13a\right) \left(2b+a\right)=0\\ \Leftrightarrow\left\{{}\begin{matrix}b=13a\\a=-2b\end{matrix}\right..\)

Đến đây bạn thay ngược $x$ trở lại và giải tiếp nhé.

 

 

29 tháng 11 2022

Bạn nhân chéo rồi rút gọn thì được:

\(x^4-3x^3+3x+1=0\\ \Leftrightarrow(x^2-2x-1)(x^2-x-1)=0\)

Bạn tự giải tiếp nhé.

1 tháng 12 2022

GDgfdsgdfggdffdv

29 tháng 11 2022

https://olm.vn/cau-hoi/cmr-sqrt2sqrt3sqrt4sqrtsqrt2000-3.81719160658

Câu hỏi đã có người trả lời ở đây bạn nhé

DD
28 tháng 11 2022

\(\sqrt{a^2-b^2}+\sqrt{2ab-b^2}>\sqrt{a^2-b^2}+\sqrt{2b^2-b^2}\)

\(=\sqrt{a^2-b^2}+\sqrt{b^2}>\sqrt{a^2-b^2+b^2}=\sqrt{a^2}=a\).