Chứng minh rằng các phân số sau bằng nhau:

a)  1717 2929   v à   171717 292929

b)  3210 − 34 4170 − 41   v à   6420 − 68 8340 − 82

c)  2106 7320 ,   4212 14640   v à   6318 21960

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.

Some kinds of fish live in fresh water. Others live in sea water.

A. Some kinds of fish live in fresh water, for others live in sea water.

B. Some kinds of fish live in fresh water, and others live in sea water.

C. Some kinds of fish live in fresh water, or others live in sea water.

D. Some kinds of fish live in fresh water, so others live in sea water.

\(x^2-4x+1\\ =x^2-4x+4-3\\ =\left(x-2\right)^2-3\)

Ta có:\(\left(x-2\right)^2\ge0\\ \Rightarrow\left(x-2\right)^2-3\ge-3\\\)

Vậy GTNN A=-3 ⇔x=2

đi mà hỏi mấy tiệm xăng ấy!!

Mark the letter A, B, C or D to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions.

A. graduate 

B. mandatory

C. explode

D. persuade