Ôn tập chương 1: Căn bậc hai. Căn bậc ba
Các câu hỏi tương tự
Rút gọn các biểu thức sau :
a) left(sqrt{8}-3sqrt{2}+sqrt{10}right)sqrt{2}-sqrt{5}
b) 0,2sqrt{left(-10right)^2.3}+2sqrt{left(sqrt{3}-sqrt{5}right)^2}
c) left(dfrac{1}{2}sqrt{dfrac{1}{2}}-dfrac{3}{2}sqrt{2}+dfrac{4}{5}sqrt{200}right):dfrac{1}{8}
d) 2sqrt{left(sqrt{2}-3right)^2}+sqrt{2.left(-3right)^2}-5sqrt{left(-1right)^4}
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Rút gọn các biểu thức sau :
a) \(\left(\sqrt{8}-3\sqrt{2}+\sqrt{10}\right)\sqrt{2}-\sqrt{5}\)
b) \(0,2\sqrt{\left(-10\right)^2.3}+2\sqrt{\left(\sqrt{3}-\sqrt{5}\right)^2}\)
c) \(\left(\dfrac{1}{2}\sqrt{\dfrac{1}{2}}-\dfrac{3}{2}\sqrt{2}+\dfrac{4}{5}\sqrt{200}\right):\dfrac{1}{8}\)
d) \(2\sqrt{\left(\sqrt{2}-3\right)^2}+\sqrt{2.\left(-3\right)^2}-5\sqrt{\left(-1\right)^4}\)
1) Rút gọn:
a) A sqrt{5-2sqrt{3-sqrt{3}}}-sqrt{3+sqrt{3}}+sqrt{2+sqrt{3}}
b) B sqrt{13+sqrt{2}+5sqrt{1+2sqrt{2}}}+sqrt{13+sqrt{2}+5sqrt{1+2sqrt{2}}}
c) C dfrac{sqrt{21+3sqrt{5}}+sqrt{21-3sqrt{5}}}{sqrt{21}+6sqrt{11}}+sqrt{11-6sqrt{2}}
d) D left(sqrt{8+2sqrt{10+2sqrt{5}}}+sqrt{8-2sqrt{10+2sqrt{5}}}right).sqrt{dfrac{2+2sqrt{5}}{2+sqrt{5}}}
e) E dfrac{left(27+10sqrt{2}right)sqrt{27-10sqrt{2}}-left(27-10sqrt{2}right)sqrt{27+10sqrt{2}}}{left(sqrt{sqrt{13}-3}+sqrt{sqrt{13}+3}right):sqrt{sqrt...
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1) Rút gọn:
a) A = \(\sqrt{5-2\sqrt{3-\sqrt{3}}}-\sqrt{3+\sqrt{3}}+\sqrt{2+\sqrt{3}}\)
b) B = \(\sqrt{13+\sqrt{2}+5\sqrt{1+2\sqrt{2}}}+\sqrt{13+\sqrt{2}+5\sqrt{1+2\sqrt{2}}}\)
c) C = \(\dfrac{\sqrt{21+3\sqrt{5}}+\sqrt{21-3\sqrt{5}}}{\sqrt{21}+6\sqrt{11}}+\sqrt{11-6\sqrt{2}}\)
d) D = \(\left(\sqrt{8+2\sqrt{10+2\sqrt{5}}}+\sqrt{8-2\sqrt{10+2\sqrt{5}}}\right).\sqrt{\dfrac{2+2\sqrt{5}}{2+\sqrt{5}}}\)
e) E = \(\dfrac{\left(27+10\sqrt{2}\right)\sqrt{27-10\sqrt{2}}-\left(27-10\sqrt{2}\right)\sqrt{27+10\sqrt{2}}}{\left(\sqrt{\sqrt{13}-3}+\sqrt{\sqrt{13}+3}\right):\sqrt{\sqrt{13}+2}}\)
Bài 1 :tính giá trị của biểu thức
a) left(sqrt{5}+sqrt{2}right)left(3sqrt{2}-1right)
b) 3sqrt{50}-2sqrt{75}-4dfrac{sqrt{54}}{sqrt{3}}-3sqrt{dfrac{1}{3}}
c) sqrt{left(sqrt{3}-3right)^2}+sqrt{4+2sqrt{3}}
d) sqrt{48-2sqrt{135}}-sqrt{45}+sqrt{18}
e)dfrac{5sqrt{2}-2sqrt{5}}{sqrt{5}-sqrt{2}}+dfrac{6}{2-sqrt{10}}-dfrac{20}{sqrt{10}}
Bài 2 :Tính:
a) 3sqrt{2x}-5sqrt{8x}+7sqrt{18x}
b) left(2sqrt{3}+4right)left(sqrt{3}-2right)
c) sqrt{3+2sqrt{2}}+sqrt{left(sqrt{2}-2right)^2}
d)sqrt{4-sqrt{15}}-sq...
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Bài 1 :tính giá trị của biểu thức
a) \(\left(\sqrt{5}+\sqrt{2}\right)\left(3\sqrt{2}-1\right)\)
b) \(3\sqrt{50}-2\sqrt{75}-4\dfrac{\sqrt{54}}{\sqrt{3}}-3\sqrt{\dfrac{1}{3}}\)
c) \(\sqrt{\left(\sqrt{3}-3\right)^2}+\sqrt{4+2\sqrt{3}}\)
d) \(\sqrt{48-2\sqrt{135}}-\sqrt{45}+\sqrt{18}\)
e)\(\dfrac{5\sqrt{2}-2\sqrt{5}}{\sqrt{5}-\sqrt{2}}+\dfrac{6}{2-\sqrt{10}}-\dfrac{20}{\sqrt{10}}\)
Bài 2 :Tính:
a) \(3\sqrt{2x}-5\sqrt{8x}+7\sqrt{18x}\)
b) \(\left(2\sqrt{3}+4\right)\left(\sqrt{3}-2\right)\)
c) \(\sqrt{3+2\sqrt{2}}+\sqrt{\left(\sqrt{2}-2\right)^2}\)
d)\(\sqrt{4-\sqrt{15}}-\sqrt{4+\sqrt{15}}+\sqrt{6}\)
e)\(\left(\dfrac{5-\sqrt{5}}{\sqrt{5}}-2\right)\left(\dfrac{4}{1+\sqrt{5}}+4\right)\)
f) \(\dfrac{1}{5}\sqrt{50}-2\sqrt{96}-\dfrac{\sqrt{30}}{\sqrt{15}}+12\sqrt{\dfrac{1}{6}}\)
Bài 1 : Thực hiện phép tính , rút gọn biểu thức
A (sqrt{5}-2)(sqrt{5}+2)
B (sqrt{5} +sqrt{3})(5-sqrt{15})
C (sqrt{45}+sqrt{63})(sqrt{7}-sqrt{5})
D dfrac{1}{sqrt{3}+1}+dfrac{1}{sqrt{3}-1}
E dfrac{5+sqrt{5}}{5-sqrt{5}}+dfrac{5-sqrt{5}}{5+sqrt{5}}
F dfrac{sqrt{3}}{sqrt{sqrt{3}+1}-1}-dfrac{sqrt{3}}{sqrt{sqrt{3}+1}+1}
G sqrt{left(2-sqrt{3}right)^2}+sqrt{4-2sqrt{3}}
H sqrt{2-sqrt{3}}-sqrt{2+sqrt{3}}
I sqrt{dfrac{3-sqrt{5}}{3+sqrt{5}}}-sqrt{dfrac{3+sqrt{5}}{3-sqrt{5}}}
K sqrt{3+sqrt...
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Bài 1 : Thực hiện phép tính , rút gọn biểu thức
A = (\(\sqrt{5}\)-2)(\(\sqrt{5}\)+2)
B = (\(\sqrt{5}\) +\(\sqrt{3}\))(5-\(\sqrt{15}\))
C = (\(\sqrt{45}+\sqrt{63}\))(\(\sqrt{7}-\sqrt{5}\))
D = \(\dfrac{1}{\sqrt{3}+1}+\dfrac{1}{\sqrt{3}-1}\)
E = \(\dfrac{5+\sqrt{5}}{5-\sqrt{5}}+\dfrac{5-\sqrt{5}}{5+\sqrt{5}}\)
F = \(\dfrac{\sqrt{3}}{\sqrt{\sqrt{3}+1}-1}-\dfrac{\sqrt{3}}{\sqrt{\sqrt{3}+1}+1}\)
G = \(\sqrt{\left(2-\sqrt{3}\right)^2}+\sqrt{4-2\sqrt{3}}\)
H = \(\sqrt{2-\sqrt{3}}-\sqrt{2+\sqrt{3}}\)
I = \(\sqrt{\dfrac{3-\sqrt{5}}{3+\sqrt{5}}}-\sqrt{\dfrac{3+\sqrt{5}}{3-\sqrt{5}}}\)
K = \(\sqrt{3+\sqrt{5}}+\sqrt{7-3\sqrt{5}}-\sqrt{2}\)
Giải PT:
a) -5x+7\(\sqrt{x}\) +12=0
b) \(\dfrac{1}{3}\)\(\sqrt{4x^2-20}\) +2\(\sqrt{\dfrac{x^2-5}{9}}\) -3\(\sqrt{x^2-5}=0\)
c) \(\sqrt{9x+27}+5\sqrt{x+3}-\dfrac{3}{4}\sqrt{16x+48}=5\)
d) \(\sqrt{49x-98}-14\sqrt{\dfrac{x-2}{49}}=3\sqrt{x-2}+8\)
rút gọn
a) \(\sqrt{8+\sqrt{55}}-\sqrt{8-\sqrt{55}}-\sqrt{125}\)
b) \(\left(\sqrt{7-3\sqrt{5}}\right)\left(7+3\sqrt{5}\right)\left(3\sqrt{2}+\sqrt{10}\right)\)
c) \(\left(\sqrt{14}-\sqrt{10}\right)\left(6-\sqrt{35}\right)\left(\sqrt{6+\sqrt{35}}\right)\)
a) \(\sqrt{243}-\dfrac{1}{2}\sqrt{12}-2\sqrt{75}+2\sqrt{27}\)
b) \(\left(2+\sqrt{6}\right)\sqrt{7-4\sqrt{3}}\)
c) \(\sqrt{\dfrac{\sqrt{5}}{8\sqrt{5}+3\sqrt{35}}}.\left(3\sqrt{2}+\sqrt{14}\right)\)
Dạng 3.Chứng minh đẳng thức
Bài 1: CM
a)\(\left(4+\sqrt{15}\right)\left(\sqrt{10}-\sqrt{6}\right)\sqrt{4-\sqrt{15}}=2\)
b)\(\left(5+\sqrt{21}\right)\left(\sqrt{14}-\sqrt{6}\right)\sqrt{5-\sqrt{21}}=8\)
Bài 2 :CM
\(\dfrac{\sqrt{\sqrt{5}+2}+\sqrt{\sqrt{5}-2}}{\sqrt{2}}=\sqrt{\sqrt{5}+1}\)
Rút gọn
a) \(\left(\dfrac{\sqrt{5}-2}{\sqrt{5}+2}+1\right).\dfrac{1}{2}+\sqrt{\left(2-4\sqrt{5}\right)^2}\)
b) \(\left(4\sqrt{2}+\sqrt{30}\right).\left(\sqrt{5}-\sqrt{3}\right).\sqrt{4-\sqrt{15}}\)