CMR: ab + ba chia hết cho 11 

ab + ba 

= 10a + b + 10b + a

= (10a + a) + (10b + b)

= 11a + 11b

chia hết cho 11

Cho các chất :

Thứ tự tăng dần nhiệt độ sôi của các chất là :

A. (III) < (II)  < (I).

B. (I) < (II) < (III).

C. (II)  < (I)  < (III).

D. (II) < (III) < (I).

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My city - Ho Chi Minh city, has bad traffic problems.

There are so many vehicles on the streets and alleys, from buses, cars, to motorbikes, bicycles. The city has the most motorbikes in this country.

Moreover, the streets are very narrow and bad. They are easily flooded when it rains so heavily. The streets and alleys become bumpy after the rain.

Many traffic users don’t obey the traffic rules. They usually drive and ride very dangerously.

As a result, there are traffic accidents every dav in this city.

My name’s Pham Nhat An. I’m 22 years old and I’m single. I have just graduated from university in August with the major in accounting. I got 3 months experience as an internship at A company. I like reading books and cooking. I’m a careful and hard-working person. I’m eager to learn new things and willing to work in team. I easily adapt to with new working environment and take initiative in work

My city - Ho Chi Minh city, has bad traffic problems.

There are so many vehicles on the streets and alleys, from buses, cars, to motorbikes, bicycles. The city has the most motorbikes in this country.

Moreover, the streets are very narrow and bad. They are easily flooded when it rains so heavily. The streets and alleys become bumpy after the rain.

Many traffic users don’t obey the traffic rules. They usually drive and ride very dangerously.

As a result, there are traffic accidents every dav in this city.

Hợp chất hữu cơ X có công thức phân tử C₉H₁₆O₄. Khi thủy phân trong môi trường kiềm thu được một muối mà từ muối này điều chế trực tiếp được axit dùng sản xuất tơ nilon-6,6. Số công thức cấu tạo thoả mãn là

A. 4

B. 2

C. 3

D. 1

Thông qua Uỷ ban thường vụ quốc hội

Ban hành vào ngày: 6-9-1972