Rút gọn
a) \(\sqrt{13+6.\sqrt{4+\sqrt{9-4\sqrt{2}}}}\)
b) (\(\frac{x-\sqrt{x}}{\sqrt{x}-1}\)+ 2) .( 2- \(\frac{\sqrt{x}+x}{1+\sqrt{x}}\))
Những câu hỏi liên quan
Rút gọn
a) \(\sqrt{13+6.\sqrt{4+\sqrt{9-4\sqrt{2}}}}\)
b) (\(\frac{x-\sqrt{x}}{\sqrt{x}-1}\)+ 2) .( 2- \(\frac{\sqrt{x}+x}{1+\sqrt{x}}\))
\(a,\sqrt{13+6\sqrt{4+\sqrt{9-4\sqrt{2}}}}\)
\(=\sqrt{13+6\sqrt{4+\sqrt{1-2.2\sqrt{2}+\left(2\sqrt{2}\right)^2}}}\)
\(=\sqrt{13+6\sqrt{4+\sqrt{\left(2\sqrt{2}-1\right)^2}}}\)
\(=\sqrt{13+6\sqrt{4+2\sqrt{2}-1}}\)
\(=\sqrt{13+6\sqrt{3+2\sqrt{2}}}\)
\(=\sqrt{13+6\sqrt{1+2\sqrt{2}+2}}\)
\(=\sqrt{13+6\sqrt{\left(1+\sqrt{2}\right)^2}}\)
\(=\sqrt{13+6\left(1+\sqrt{2}\right)}=\sqrt{13+6+\sqrt{12}}\)
\(=\sqrt{19+2\sqrt{3}}\)
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a) = \(\sqrt{13+6\sqrt{4+\sqrt{9-4\sqrt{2}}}}\)
= \(\sqrt{13+6\sqrt{4+\sqrt{8-2.2\sqrt{2}+1}}}\)
= \(\sqrt{13+6\sqrt{4+\sqrt{\left(2\sqrt{2}-1\right)^2}}}\)
= \(\sqrt{13+6\sqrt{4+2\sqrt{2}-1}}\)
= \(\sqrt{13+6\sqrt{2+2\sqrt{2}+1}}\)
= \(\sqrt{13+6\left(\sqrt{2}+1\right)}\)
= \(\sqrt{13+6\sqrt{2}+6}=\sqrt{19+6\sqrt{2}}\)
= \(\sqrt{18+2.3\sqrt{2}+1}\)
= \(\sqrt{\left(3\sqrt{2}+1\right)^2}\)
= \(3\sqrt{2}+1\)
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\(b,\left(\frac{x-\sqrt{x}}{\sqrt{x}-1}+2\right)\left(2-\frac{\sqrt{x}+x}{1+\sqrt{x}}\right).\)
\(=\left(2+\frac{\sqrt{x}\left(\sqrt{x}-1\right)}{\sqrt{x}-1}\right)\left(2-\frac{\sqrt{x}\left(1+\sqrt{x}\right)}{1+\sqrt{x}}\right)\)
\(=\left(2+\sqrt{x}\right)\left(2-\sqrt{x}\right)=4-x\)
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Rút gọn
a) \(\sqrt{13+6.\sqrt{4+\sqrt{9-4\sqrt{2}}}}\)
b) (\(\frac{x-\sqrt{x}}{\sqrt{x}-1}\)+ 2) .( 2- \(\frac{\sqrt{x}+x}{1+\sqrt{x}}\))
Cho biểu thức: \(P=\left(\frac{\sqrt{x}-3}{2-\sqrt{x}}+\frac{\sqrt{x}+2}{3+\sqrt{x}}-\frac{9-x}{x+\sqrt{x}-6}\right):\left(1-\frac{3\sqrt{x}-9}{x-9}\right)\)
a)Rút gọn biểu thức
b)Tính P với \(x=\frac{\sqrt{4+2\sqrt{3}}\left(\sqrt{x}-1\right)}{\sqrt{6+2\sqrt{5}-\sqrt{5}}}\)
Mình ghi nhầm. \(x=\frac{\sqrt{4+2\sqrt{3}}.\left(\sqrt{3}-1\right)}{\sqrt{6+2\sqrt{5}}-\sqrt{5}}\)nhé
Bài 1: Tính :Csqrt{frac{3sqrt{3}-4}{2sqrt{3}+1}}-sqrt{frac{sqrt{3}+4}{5-2sqrt{3}}}Bfrac{1}{sqrt{1}+sqrt{2}}+frac{1}{sqrt{2}+sqrt{3}}+frac{1}{sqrt{3}+sqrt{4}}+....+frac{1}{sqrt{99}+sqrt{100}}Dsqrt{1+sqrt{3+sqrt{13+4sqrt{3}}}}+sqrt{1-sqrt{3-sqrt{13-4sqrt{3}}}}Bài 2 : Cho Pleft(frac{1}{sqrt{x}-1}+frac{x-sqrt{x}+6}{x+sqrt{x}-2}right):left(frac{sqrt{x}+1}{sqrt{x}+2}+frac{x-sqrt{x}-2}{x+sqrt{x}+2}right) a, Rút gọn P b, Tìm GTNNc, Tìm x để P.frac{x-1}{x^2+8x} -2
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Bài 1: Tính :
\(C=\sqrt{\frac{3\sqrt{3}-4}{2\sqrt{3}+1}}-\sqrt{\frac{\sqrt{3}+4}{5-2\sqrt{3}}}\)
\(B=\frac{1}{\sqrt{1}+\sqrt{2}}+\frac{1}{\sqrt{2}+\sqrt{3}}+\frac{1}{\sqrt{3}+\sqrt{4}}+....+\frac{1}{\sqrt{99}+\sqrt{100}}\)
\(D=\sqrt{1+\sqrt{3+\sqrt{13+4\sqrt{3}}}}+\sqrt{1-\sqrt{3-\sqrt{13-4\sqrt{3}}}}\)
Bài 2 : Cho \(P=\left(\frac{1}{\sqrt{x}-1}+\frac{x-\sqrt{x}+6}{x+\sqrt{x}-2}\right):\left(\frac{\sqrt{x}+1}{\sqrt{x}+2}+\frac{x-\sqrt{x}-2}{x+\sqrt{x}+2}\right)\)
a, Rút gọn P
b, Tìm GTNN
c, Tìm x để \(P.\frac{x-1}{x^2+8x}< -2\)
Cho biểu thức A=\(\left(1-\frac{\sqrt{x}}{\sqrt{x}+1}\right)\)và B= \(\frac{\sqrt{x}+3}{\sqrt{x}-2}+\frac{\sqrt{x}+2}{3-\sqrt{x}}-\frac{\sqrt{x}+2}{x-5\sqrt{x}+6}\) 9x>/ 0 , x khác 4 , x khác 9 )
a) Rút gọn A và tính A khi x = 1
b) Rút gọn B
Rút gọn biểu thức frac{left(sqrt{x-4sqrt{x-4}}+sqrt{x+4sqrt{x-4}}right)left(sqrt{x-1}-1right)}{sqrt{x-2sqrt{x-1}}}b,sqrt{x-2sqrt{x-1}+sqrt{x+2sqrt{x-1}}}1le xle2c, sqrt{x+6sqrt{x-9}}+sqrt{x-6sqrt{x-9}}x18d, frac{1}{2left(1+sqrt{x+2}right)}+frac{1}{2left(1-2sqrt{x+2}right)}e,frac{1}{sqrt{x+2sqrt{x-1}}}-frac{1}{sqrt{x-2sqrt{x-1}}}
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Rút gọn biểu thức
\(\frac{\left(\sqrt{x-4\sqrt{x-4}}+\sqrt{x+4\sqrt{x-4}}\right)\left(\sqrt{x-1}-1\right)}{\sqrt{x-2\sqrt{x-1}}}\)
b,\(\sqrt{x-2\sqrt{x-1}+\sqrt{x+2\sqrt{x-1}}}1\le x\le2\)
c, \(\sqrt{x+6\sqrt{x-9}}+\sqrt{x-6\sqrt{x-9}}x>18\)
d, \(\frac{1}{2\left(1+\sqrt{x+2}\right)}+\frac{1}{2\left(1-2\sqrt{x+2}\right)}\)
e,\(\frac{1}{\sqrt{x+2\sqrt{x-1}}}-\frac{1}{\sqrt{x-2\sqrt{x-1}}}\)
a) Tính giá trị biểu thức:
N=\(\frac{\sqrt{15-10\sqrt{2}}+\sqrt{13+4\sqrt{10}}-\sqrt{11+2\sqrt{10}}}{2\sqrt{3+2\sqrt{2}}+\sqrt{9-4\sqrt{2}}+\sqrt{12+8\sqrt{2}}}\)
b)Rút gọn biểu thức:
A=\(\frac{x^3-3x+\left(x^2-1\right)\sqrt{x^2-4}-2}{x^3-3x+\left(x^2-1\right)\sqrt{x^2-4}+2}\),trị x>2
Tìm ĐKXĐ và rút gọn biểu thứcAfrac{left(sqrt{a}+sqrt{b}right)^2-4sqrt{ab}}{sqrt{a}-sqrt{b}}-frac{asqrt{b}+bsqrt{a}}{sqrt{ab}}Bleft(frac{2sqrt{x}-x}{xsqrt{x}-1}-frac{1}{sqrt{x}-1}right):frac{x-1}{x+sqrt{x}+1}Cleft(1-frac{x-3sqrt{x}}{x-9}right):left(frac{sqrt{x}-3}{2-sqrt{x}}+frac{sqrt{x}-2}{3+sqrt{x}}-frac{9-x}{x+sqrt{x}-6}right)Dleft(frac{sqrt{x}}{3+sqrt{x}}+frac{x+9}{9-x}right):left(frac{3sqrt{x}+1}{x-3sqrt{x}}-frac{1}{sqrt{x}}right)CM rằng GT của bthức A ko phụ thuộc vào aTìm x để C 4Tìm x sa...
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Tìm ĐKXĐ và rút gọn biểu thức
\(A=\frac{\left(\sqrt{a}+\sqrt{b}\right)^2-4\sqrt{ab}}{\sqrt{a}-\sqrt{b}}-\frac{a\sqrt{b}+b\sqrt{a}}{\sqrt{ab}}\)
\(B=\left(\frac{2\sqrt{x}-x}{x\sqrt{x}-1}-\frac{1}{\sqrt{x}-1}\right):\frac{x-1}{x+\sqrt{x}+1}\)
\(C=\left(1-\frac{x-3\sqrt{x}}{x-9}\right):\left(\frac{\sqrt{x}-3}{2-\sqrt{x}}+\frac{\sqrt{x}-2}{3+\sqrt{x}}-\frac{9-x}{x+\sqrt{x}-6}\right)\)
\(D=\left(\frac{\sqrt{x}}{3+\sqrt{x}}+\frac{x+9}{9-x}\right):\left(\frac{3\sqrt{x}+1}{x-3\sqrt{x}}-\frac{1}{\sqrt{x}}\right)\)
CM rằng GT của bthức A ko phụ thuộc vào a
Tìm x để C = 4
Tìm x sao cho D < -1
a: \(A=\dfrac{\left(\sqrt{a}-\sqrt{b}\right)^2}{\sqrt{a}-\sqrt{b}}-\dfrac{\sqrt{ab}\left(\sqrt{a}+\sqrt{b}\right)}{\sqrt{ab}}\)
\(=\sqrt{a}-\sqrt{b}-\sqrt{a}-\sqrt{b}=-2\sqrt{b}\)
b: \(B=\dfrac{2\sqrt{x}-x-x-\sqrt{x}-1}{\left(\sqrt{x}-1\right)\left(x+\sqrt{x}+1\right)}\cdot\dfrac{x+\sqrt{x}+1}{x-1}\)
\(=\dfrac{-2x+\sqrt{x}-1}{\sqrt{x}-1}\cdot\dfrac{1}{x-1}\)
c: \(C=\dfrac{x-9-x+3\sqrt{x}}{x-9}:\left(\dfrac{3-\sqrt{x}}{\sqrt{x}-2}+\dfrac{\sqrt{x}-2}{\sqrt{x}+3}+\dfrac{x-9}{x+\sqrt{x}-6}\right)\)
\(=\dfrac{3\left(\sqrt{x}-3\right)}{x-9}:\dfrac{9-x+x-4\sqrt{x}+4+x-9}{\left(\sqrt{x}+3\right)\left(\sqrt{x}-2\right)}\)
\(=\dfrac{3}{\sqrt{x}+3}\cdot\dfrac{\left(\sqrt{x}+3\right)\left(\sqrt{x}-2\right)}{x-4\sqrt{x}+4}\)
\(=\dfrac{3}{\sqrt{x}-2}\)
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Rút gọn B=\(\left(\frac{1}{\sqrt{x}-2}-\frac{2}{\sqrt{x}+2}+\frac{x}{x\sqrt{x}-4\sqrt{x}}\right):\left(\frac{6-x}{\sqrt{x}+2}+2+\sqrt{x}\right)\)
\(B=\left(\frac{1}{\sqrt{x}-2}-\frac{2}{\sqrt{x}+2}+\frac{x}{x\sqrt{x}-4\sqrt{x}}\right):\left(\frac{6-x}{\sqrt{x}+2}+2+\sqrt{x}\right)\)
\(B=\left(\frac{\sqrt{x}+2}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}-\frac{2\left(\sqrt{x}-2\right)}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}+\frac{\sqrt{x}}{\left(\sqrt{x}-2\right)\left(\sqrt{x+2}\right)}\right):\left(\frac{6-x+2\left(\sqrt{x}+2\right)+\sqrt{x}\left(\sqrt{x}+2\right)}{\sqrt{x}+2}\right)\)
\(B=\left(\frac{\sqrt{x}+2-2\sqrt{x}+4+\sqrt{x}}{\left(\sqrt{x}+2\right)\left(\sqrt{x}-2\right)}\right):\left(\frac{6-x+2\sqrt{x}+4+x+2\sqrt{x}}{\sqrt{x}+2}\right)\)
\(B=\frac{6}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}\cdot\frac{\sqrt{x}+2}{10+4\sqrt{x}}\)
\(B=\frac{6}{\sqrt{x}-2}\cdot\frac{1}{2\left(5+2\sqrt{x}\right)}\)
B = \(\frac{3}{\left(\sqrt{x}-2\right)\left(5+2\sqrt{x}\right)}\)