Từ đề bài ta có sơ đồ:

Số bé là: \(\left(151-1\right):3=50\)

Số lớn là : 151 - 50 =101.

ĐS.

 a) \(\left(3x+2\right)^3=\left(3x\right)^3+3.\left(3x\right)^2.2+3.3x.2^2+2^3=27x^3+54x^2+36x+8\)

b) \(\left(3-2x^2\right)^3=3^3-3.3^2.2x^2+3.3.\left(2x^2\right)^2-\left(2x^2\right)^3=27-54x^2+36x^4-8x^6\)

The Maldives are a group of very small islands in the Indian Ocean, near Sri Lanka. It has the smallest (1) __________ of any Asian countries. There are about 1200 islands and there are people living on 200 of them. About 400,000 people live in the Maldives and 75,000 of them are (2)__________ the capital island, Mal. Mal is different from the other islands in the Maldives because it doesn't have any beaches. In fact, there is a small wall (3) __________ goes around the whole islands.

It is very easy to get around the islands. When you (4) __________ on the airpot island, you can take a dhoni and go to Mal. This is a small boat used for (5) __________ around the islands. Dhoni taxis go from the airport island to the capital island every fifteen minutes and (6) __________ midnight every half an hour. You can use these boats to visit other islands, too.

The Maldives are a popular place for scuba diving (7) __________ there are many wonderful fish in the water to see. Also, the water is very clear so when you are (8) __________ you can see for more than 500 metres! There are many professionals diving schools with instructors. They speak many languages, so you can (9) __________ someone to help you. Of course, that’s not all you can do on this beautiful islands. You can go whale and dolphin (10) __________, fishing, surfing, snorkeling, hiking or explore the towns.

1. A. nation B. population C. area D. inhabitant

2. A. in B. at C. above D. on

3. A. who B. where C. that D. it

4. A. arrive B. travel C. depart D. leave

5. A. education B. transportation C. production D. translation

6. A. at B. before C. on D. after

7. A. although B. because C. however D. furthermore

8. A. underwater B. underlevel C. undersea D. Underneath

9. A. look B. see C. find D. hold

10. A. playing B. catching C. hearing D. watching

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xx' và yy' cắt nhau tại O

Ot và Ot' lần lượt là 2 tia phân giác của góc xOy và x'Oy'

Giải:

Ot là tia phân giác của góc xOy

=> xOt = tOy = \(\frac{xOy}{2}\)

Ot' là tia phân giác của góc x'Oy'

=> x'Ot' = t'Oy' = \(\frac{x'Oy'}{2}\)

mà góc xOy = góc x'Oy' (2 góc đối đỉnh)

=> góc xOt = góc x'Ot'

mà góc xOt' + góc t'Ox' = 180⁰

=> góc xOt + góc t'Ox' = 180⁰

=> góc xOt và góc t'Ox' kề bù

=> Ot và Ot' là 2 tia đối nhau.

Chúc bạn học tốt!

=> (x-1)(x-2)>0

TH1 :

x-1 > 0 => x \(\ge\) 1

x-2 > => x \(\ge\)2

TH2 :

x - 1 < 0 => x < 1

x - 2 < 0=> x < 2