1) Vì x=25 thỏa mãn ĐKXĐ nên Thay x=25 vào biểu thức \(A=\dfrac{\sqrt{x}-2}{x+1}\), ta được:

\(A=\dfrac{\sqrt{25}-2}{25+1}=\dfrac{5-2}{25+1}=\dfrac{3}{26}\)

Vậy: Khi x=25 thì \(A=\dfrac{3}{26}\)

2) Ta có: \(B=\dfrac{\sqrt{x}-3}{\sqrt{x}+1}+\dfrac{2x+8\sqrt{x}-6}{x-\sqrt{x}-2}\)

\(=\dfrac{\left(\sqrt{x}-3\right)\left(\sqrt{x}-2\right)}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+1\right)}+\dfrac{2x+8\sqrt{x}-6}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+1\right)}\)

\(=\dfrac{x-5\sqrt{x}+6+2x+8\sqrt{x}-6}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+1\right)}\)

\(=\dfrac{3x+3\sqrt{x}}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+1\right)}\)

\(=\dfrac{3\sqrt{x}\left(\sqrt{x}+1\right)}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+1\right)}\)

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

câu 3 chứ

1 She failed to do everything she was supposed to do

2 There is no likelihood that anyone will apply for this post

3 He succeeded in finishing the English test in time

4 There is no likelihood that the situation will improve in the near future

5 There is a chance that you will get what you want there

6 Don't check your answers before answering all the questions

7 I won't give an opinion before thinking this through

8 The judge will decide after hearing all the evidence

9  I won't be able to have a holiday until I save enough money

10 There is little likelihood that my sister will win the first prize in the singing contest

11 He made no reference of his new job when I last spoke to him

1 She failed to do everything she was supposed to do

2 There is no likelihood that anyone will apply for this post

3 He succeeded in finishing the English test in time

4 There is no likelihood that the situation will improve in the near future

5 There is a chance that you will get what you want there

6 Don't check your answers before answering all the questions

7 I won't give an opinion before thinking this through

8 The judge will decide after hearing all the evidence

9  I won't be able to have a holiday until I save enough money

10 There is little likelihood that my sister will win the first prize in the singing contest

11 He made no reference of his new job when I last spoke to him

Câu 16: A

Câu 14: C

Câu 12: A

1: Xét (O) có

DC là tiếp tuyến

DA là tiếp tuyến

Do đó: DC=DA

Xét (O) có

EC là tiếp tuyến

EB là tiếp tuyến

Do đó: EC=EB

Ta có: DC+EC=DE

nên DE=AC+EB

mình làm những bài bn chưa lm nhé

9B

10A

bài 2

have repainted

bàii 3

ride - walikking

swimming

watch

2 have repainted

4 have done 

8 have stepped

9 have you ever played

7) 1 riding -walking

2 swimming

3 watching

8)

2 my mother doesn't like listening to music

5 doing more exercises makes you healthier

còn lại ok nha

chịu ???????????????????