Giải phương trình

\(\sqrt{x^2-2x+4}=\sqrt{2-x}\)

Giải phương trình

\(\sqrt{x-2\sqrt{x-2}-1}-\sqrt{x+2+4\sqrt{x-2}+3}=0\)

Rút gọn:

\(\sqrt{2+\sqrt{3}}-\sqrt{2-\sqrt{3}}\)

Rút gọn :

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

Rút gọn :

\(\left(\dfrac{a-2\sqrt{ab}}{a+2b-3\sqrt{ab}}-\dfrac{2b+\sqrt{ab}}{a+2b+3\sqrt{ab}}\right):\left(\dfrac{1}{\sqrt{a}}+\dfrac{1}{\sqrt{b}}-\dfrac{2}{\sqrt{a}+\sqrt{b}}\right)\)

chọn câu trả lời sai:

Câu 1:

A. George isn't looking very well these days, is he?

B. George isn't looking very healthy these days, is he?

C. Bright eyes are a sign of a healthy dog.

D. Bright eyes are a sign of a well dog.

Câu 2:

A. I don't like hospitals. They're full of ill people

B. I don't like hospitals. They're full of sick people

C. Dave's not coming to work today. He's ill

D. Dave's not coming to work today. He's sick

Câu 3:

A. The thief walked quietly past the sleeping dogs

B. The thief walked quietly past the asleep dogs

C. Shh! The children are asleep

D. Shh! The children are sleeping

Rút gọn

a) \(\dfrac{\sqrt{\sqrt{5}+2}+\sqrt{\sqrt{5}-2}}{\sqrt{\sqrt{5}+1}}-\sqrt{3-2\sqrt{2}}\)

b) \(\dfrac{2+\sqrt{3}}{\sqrt{2}+2+\sqrt{3}}+\dfrac{2-\sqrt{3}}{\sqrt{2}-2-\sqrt{3}}\)

c) \(\dfrac{\sqrt{7+\sqrt{5}}+\sqrt{7-\sqrt{5}}}{\sqrt{7+2\sqrt{11}}}\)

Rút gọn

\(\dfrac{\sqrt{2}}{\sqrt{\sqrt{2}+1}-1}-\dfrac{\sqrt{2}}{\sqrt{\sqrt{2}+1}+1}\)

Trục căn thức

\(\dfrac{\sqrt{a}}{\sqrt{a}+1-\sqrt{b}}\)

Rút gọn

\(a.\sqrt{49-5\sqrt{96}}-\sqrt{49+5\sqrt{96}}\)

b. \(\sqrt{36-12\sqrt{5}}\)