Rút gọn các biểu thức sau:
2a2 -5a với a < 0
2√a2 - 5a = 2|a| - 5a
= -2a - 5a = -7a (do a < 0 nên |a| = -a)
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.
We should decorate our living room with _____ orange banner. We also need ________ ribbons, balloons, party hats and costume.
I think that ______ cauliflower is not enough for 3 people. Let’s buy one more.