Giá trị của biểu thức 16 : 2^ 2 + ( 15 ^3 ) ^0 + 3 ^14 : 3 ^12 

14.
12.
13.
15.

một dây dẫn đồng chất, chiều dài l, tiết diện S có điện trở R= 12Ω. Nếu gập đôi lại thành một dây có chiều dài giảm còn một nửa thì điện trở của dây đó là bao nhiêu??

Cumulative Vocabulary and Grammar
Choose the correct option (A or B) to complete the conversation.
Anna: Hi, Nina. This is Steffen. He’s from Germany and (1) with us for a month.
Nina: Hi Anna. Hi Steffen. It’s nice to meet you.
Steffen: Nice to meet you too.
Nina: (2) Plymouth?
Steffen: Yes, I do. It’s a nice town. I love (3) and there are lots of beaches here where I can do that.
Nina: That’s great. My (4) loves the water too. He’s 16. How old are you?
Steffen: I’m 14. What about you? What do you do in your free time?
Nina: I like playing music.
Steffen: (5) instrument do you play?
Nina: The piano and the guitar.
Steffen: I (6) the guitar too.
Nina: You can join our music group. It’s (7) on Tuesday, but it’s sometimes on Thursday.
Steffen: Thanks. That sounds fun.
Anna: Are you busy? (8) time for a meal?
Nina: Yes. I’d like (9) burger and (10) juice.
Anna and Steffen: Me too!
1 A he’s staying B he stays C staying
2 A Would you like B Do you like C Are you like
3 A skateboarding B surfing C martial arts
4 A sister B aunt C brother
5 A What B Where C Who
6 A do B play C go
7 A usually B always C never
8 A Got you B Have you got C Do you
9 A a B any C many
10 A many B some C much

Chia động từ trong ngoặc ở thì thích hợp:

1. ……….. you often …………….(watch) TV?

2. I usually ………………….. (go) shopping on weekend.

3. Hai often ……………………(wash) his face at 6.15.

4. Thanh and Mai  ……………………(see) a movie at the moment.

5. ………….he often ……………………(take) a bus to school?

6. We ……………………(be) student in class 8A.

7 He  ……………………(take) a taxi to the airport tomorrow.

8 She ……………………(go) to work by bus tomorrow.

9. .…………..you ……………………(see) the doctor next week

10 Mai and Nam ……………………(go) to the movie theater tomorrow evening.

Rút gọn các biểu thức sau :

a) √(2-√3)^2
b) √(3-√11)^2

c) 2√a^2 với a>=0

d) 3√(a-2)^2 với a>2

e) √a^6 với a<0

f) 2√a^2 -5a với a<0

g) √25a^2 + 3a với a>=0

h) √9a^4 + 3a^2

i) 5√4a^6 - 3a^3 với a<0

j) 3√(3-a)^2 - 2a với a>3