Cho dãy số (un) với   , trong đó a là các hằng số. Để dãy số (un) có giới hạn bằng 2, giá trị của a là:
A. 4
B. 6
C. 8
D. 10

Cho (un) và (vn) là hai dãy số có giới hạn. Khẳng định đúng là
A.
B.
C.
D.

Cho hàm số . Tìm khẳng định đúng trong các khẳng định sau:
.
liên tục tại 
gián đoạn tại 
A. Chỉ và  
B. Chỉ và  
C. Chỉ  
D. Chỉ (II)

Rút gọn $S=1+{{\cos }^{2}}x+{{\cos }^{4}}x+{{\cos }^{6}}x+\cdots +{{\cos }^{2n}}x+\cdots $ với$\cos x\ne \pm 1.$
A. $S={{\sin }^{2}}x.$ 
B. $S={{\cos }^{2}}x.$ 
C. $S=\frac{1}{{{\sin }^{2}}x}.$ 
D. $\displaystyle S=\frac{1}{{{\cos }^{2}}x}.$

Giá trị của giới hạn $\underset{x\to -\infty }{\mathop{\lim }}\,\left( x-{{x}^{3}}+1 \right)$ là 
A. $1.$ 
B. $-\infty .$ 
C. $0.$ 
D. $+\infty .$

Choose one sentence that has the same meaning to the root one:
He doesn’t go to school on time. They don’t go to school one time.
A. He doesn’t go to school on time and so does they.
B. He doesn’t go to school on time and neither does they.
C. He doesn’t go to school on time and neither do they.
D. He doesn’t go to school on time and either don’t they.

Tìm khẳng định đúng trong các khẳng định sau
.  liên tục trên .
.  liên tục trên khoảng .
.  liên tục trên đoạn .
A. Chỉ  đúng. 
B. Chỉ  và . 
C. Chỉ  và  
D. Chỉ  và

Choose one sentence that has the same meaning as the root one:
I was the last to know about the accident.
A. At last I knew about the accident.
B. I wasn't informed of the accident at all.
C.  Everyone heard about the accident before I did. 
D. The last thing I must know now is the accident.

Choose one sentence that has the same meaning to the root one:
It is believed that the man escaped in a stolen car.
A. The man is believed to escape in a stolen car.
B. The man is believed to have escaped in a stolen car. 
C. The man believed to escaped in a stolen car.
D. They believed that the man stole the car.

Choose one sentence that has the same meaning as the root one:
Can you take care of my dog while I’m on holiday?
A. Can you look after my dog while I’m on holiday?
B. Are you able to take after my dog while I’m on holiday?
C. Can you look into my dog whiles I’m on holiday?
D. Are you able to take up my dog while I’m on holiday?