Câu 16: A

Câu 14: C

Câu 12: A

Câu 5: D

Câu 6: B

Câu 7: B

Câu 9: A

1A

2D

3C

4B

5A

Bạn để ý \(\left(2\sqrt{x}-1\right)\left(\sqrt{x}+4\right)=2x+7\sqrt{x}-4\)

Bạn chỉ cần quy đồng lên rồi tính thôi.

9) Ta có: \(\dfrac{\sqrt{x}+2}{x-5\sqrt{x}+6}-\dfrac{\sqrt{x}+3}{2-\sqrt{x}}-\dfrac{\sqrt{x}+2}{\sqrt{x}-3}\)

\(=\dfrac{\sqrt{x}+2+x-9-x+4}{\left(\sqrt{x}-2\right)\left(\sqrt{x}-3\right)}\)

\(=\dfrac{\sqrt{x}-3}{\left(\sqrt{x}-2\right)\left(\sqrt{x}-3\right)}\)

\(=\dfrac{1}{\sqrt{x}-2}\)

74. what color are his pencils?

75. when does mr tam always work?

76. who is your close friend?

77. where are they going to have dinner?

78. how many texts are they going to read?

81. what is she going to buy?

82. what does his grandmother usually tell him in the evening?

83. what does our mother buy at that clothing store?

84. when does this man bring us milk?

85. who always have dinner at home?

86. how many does she want of coffee?

87. what does mrs white always have for breakfast?

88. when do you always go to school with my friends?

89. what is mary's mother going to do?

90. what time does your mother always have breakfast?

74. What color are his pencils?

75. When does Mr.Tam work?

76. Who is your close friend?

77. Where are they going to have dinner?

78. How many texts are they going to read?

79, 80 không có phần gạch chân.

81. What is she going to buy?

82. What does his grandmother usually tell him in the evening?

83. What does your mother buy you at that clothing store?

84. When does this man bring you milk?

85. Who always have dinner at home?

86. How much coffee does she want?

87. What does Mrs.White always have for breakfast?

88. When do you always go to school with your friends?

89. Where is Mary's mother going?

90. What time does her mother always have breakfast?

Ai giúp mình với đi ạ 

exs1

1 don't have to

3 mustn't

7  don't have to

exs2

3 might

4 can't

7 might be

còn nữa ...