Underline the errors in these sentences. Rewrite each sentence.
1. Kate's brother is doctor.
..............................................
2. I ate food with Jack, and after that I went home.
...............................................
3. The milk is good for you.
...............................................
4. Can you give me an advice?
................................................
5. I've look in the box. All is broken, I'm afraid.
.................................................
6. They will have finished the new hospital until the end of May.
.................................................
7. There's a police waiting outside.
.................................................
8. I come to class with the feet.
.................................................
9. Your hair are very beautiful.
...............................................

-4/5 căn 50-25x - 2/3 căn 18-9x +6=0

Cho biểu thức: P=√x +1/√x -1 + √x -1/√x+1 - 3√x +1/√x -1

a) Rút gọn P
b) Tính giá trị của P khi x = 2

c) Tìm x để P=1/2

d) Tìm x để P=/P/

e)Tìm x để P^{^2}+P<=0

(2 căn x +1)(căn x -2)=7

8/2 cănx -1>=0   (x>=0; x khác 1/4)