xác định a sao cho 2x^3-3x^2+4x+a chia cho x-2 dư 3

rút gọn biểu thức: 1/x-2+1/x+2+x^2/x^2-3

CMR: Biểu thức sau ko phụ thuộc vào biến :x(x-2y)-(x-y)^2+y^2+3

Tìm x biết : 5(x+2)-y^2-2x=0

1/ A man in............ police uniform came across the street

A. the B. an C. a D.X

2/ Tom passed the exam! It is such .............. good news

A. X B. an C. a D. the

3/ That new drug has great ............... for the treatment of this diseas

A. significance B. significant C. significantly D. insignificant

4/ There are few ................ in the beginning but you'll solve them soon

A. ways B. diversities C. dificulties D. specialities

5/ They are all........... engineers. Every customer is satisfied with their working style

A. disturbing B bad C. delicious D. experienced