Chứng minh đẳng thức sau không phụ thuộc vào x,y : $A$ = $\frac{\sqrt{x}}{\sqrt{x}-\sqrt{y}}$ -$\frac{\sqrt{y}}{\sqrt{x}+\sqrt{y}}$ - $\frac{2y}{x-y}$ ($x$;$y$$\geq$ 0; $x$ $\neq$ y)

Choose the best answer.

I think you should buy _____  pack of mineral water instead. And you can also buy _____  snacks such as potato crisps, 3 kilos of mandarins, 2 kilos of apples, 3 bunches of bananas, ______  cookies and soft candies.

Choose the best answer.

We should decorate our living room with _____ orange banner. We also need ________  ribbons, balloons, party hats and costume.

Choose the best answer.

I think that ______ cauliflower is not enough for 3 people. Let’s buy one more.