\(\sqrt{7-4\sqrt{3}}+\dfrac{1}{2-\sqrt{3}}\)
\(=2-\sqrt{3}+2+\sqrt{3}\)
=4
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Bài 8: Rút gọn biểu thức chứa căn bậc hai
Các câu hỏi tương tự
1.1/3-2√2 + 1/2+√5 2.1/√3+√7 + 2/1-√7 3.a-2√a/2-√a 4.x√y+y√x/√x+√y
Rút gọn các bt sau
A√(5-√21) +√(5+√21)
B[(√15 -√5)/(√3 -1)]+[(5-2√2)/(2√5 -4)]
C {1+[(11-√11)/(1-√11)]}×{[(11+√11)/(1+√11)]+1}
D[√2/(√2-√3)]-[√2/(√2+√3)]
E[1/(√2 -√3)]×√[(3√2 -2√3)/(3√2+2√3)]
F√(6-2√2 +2√3 -2√6 )
G√[(6+2√5-√(29-12√5)]
H1/√3 +1/3√2 +1/√3×[(5/12)×(1/√6)]
I(√2+1)×(√2^2 +1)×(√2^4 +1)×(√2^8 +1)(√2^16 +1)
K1/(√2 +√3)+1/(√3 +√4) +1/(√4 +√5)+.....+1/(√2009 +√2010)
L{(4+√7)/[3√2 +√(4+√7)]}+{(4-√7)/[3√2 -√(4-√7)]}
Hỡi các cao nhân giúp em với em xin hậu tạ
Đọc tiếp
Rút gọn các bt sau
A=√(5-√21) +√(5+√21)
B=[(√15 -√5)/(√3 -1)]+[(5-2√2)/(2√5 -4)]
C= {1+[(11-√11)/(1-√11)]}×{[(11+√11)/(1+√11)]+1}
D=[√2/(√2-√3)]-[√2/(√2+√3)]
E=[1/(√2 -√3)]×√[(3√2 -2√3)/(3√2+2√3)]
F=√(6-2√2 +2√3 -2√6 )
G=√[(6+2√5-√(29-12√5)]
H=1/√3 +1/3√2 +1/√3×[(5/12)×(1/√6)]
I=(√2+1)×(√2^2 +1)×(√2^4 +1)×(√2^8 +1)(√2^16 +1)
K=1/(√2 +√3)+1/(√3 +√4) +1/(√4 +√5)+.....+1/(√2009 +√2010)
L={(4+√7)/[3√2 +√(4+√7)]}+{(4-√7)/[3√2 -√(4-√7)]}
Hỡi các cao nhân giúp em với em xin hậu tạ
1. Asqrt{4+sqrt{ }7}+ sqrt{4-sqrt{ }7} 2. Bdfrac{sqrt{sqrt{7-sqrt{3}}}-sqrt{sqrt{7+sqrt{3}}}}{sqrt{sqrt{7}-sqrt{2}}} 3. Csqrt{6+2sqrt{2cdotsqrt{3-sqrt{4+2sqrt{3}}}}} 4. Dsqrt{5}-sqrt{3-sqrt{29-12sqrt{5}}}...
Đọc tiếp
1. A=\(\sqrt{4+\sqrt{ }7}\)+ \(\sqrt{4-\sqrt{ }7}\) 2. B=\(\dfrac{\sqrt{\sqrt{7-\sqrt{3}}}-\sqrt{\sqrt{7+\sqrt{3}}}}{\sqrt{\sqrt{7}-\sqrt{2}}}\) 3. C=\(\sqrt{6+2\sqrt{2\cdot\sqrt{3-\sqrt{4+2\sqrt{3}}}}}\) 4. D=\(\sqrt{5}-\sqrt{3-\sqrt{29-12\sqrt{5}}}\) 5. so sánh Cho A=\(\sqrt{11+\sqrt{96}}\) B=\(\dfrac{2\sqrt{2}}{\sqrt{1+\sqrt{2-\sqrt{3}}}}\) so sánh A và B
1. Asqrt{4+sqrt{7}} +sqrt{4-sqrt{7}}
2. B dfrac{sqrt{sqrt{7-sqrt{3}}-sqrt{7+sqrt{3}}}}{sqrt{7-sqrt{2}}}
3. Csqrt{6+2sqrt{2cdotsqrt{3-sqrt{4+2sqrt{3}}}}}
4. Dsqrt{5}-sqrt{3-sqrt{29-12sqrt{5}}}
5 Edfrac{1+sqrt{5}}{sqrt{2}+sqrt{3}+sqrt{5}} +dfrac{1-sqrt{5}}{sqrt{2}-sqrt{3-sqrt{5}}}
6. so sánh Cho Asqrt{11+sqrt{96}}
B dfrac{2sqrt{2}}{1+sqrt{2-sqrt{3}}} so sánh A và b
Đọc tiếp
1. A=\(\sqrt{4+\sqrt{7}}\) +\(\sqrt{4-\sqrt{7}}\)
2. B= \(\dfrac{\sqrt{\sqrt{7-\sqrt{3}}-\sqrt{7+\sqrt{3}}}}{\sqrt{7-\sqrt{2}}}\)
3. C=\(\sqrt{6+2\sqrt{2\cdot\sqrt{3-\sqrt{4+2\sqrt{3}}}}}\)
4. D=\(\sqrt{5}-\sqrt{3-\sqrt{29-12\sqrt{5}}}\)
5 E=\(\dfrac{1+\sqrt{5}}{\sqrt{2}+\sqrt{3}+\sqrt{5}}\) +\(\dfrac{1-\sqrt{5}}{\sqrt{2}-\sqrt{3-\sqrt{5}}}\)
6. so sánh Cho A=\(\sqrt{11+\sqrt{96}}\)
B= \(\dfrac{2\sqrt{2}}{1+\sqrt{2-\sqrt{3}}}\) so sánh A và b
tính1.left(sqrt{15}-2sqrt{3}right)^2+12sqrt{5}2.3sqrt{2}left(4-sqrt{2}right)+3left(1-2sqrt{2}right)^23.dfrac{1}{2}left(sqrt{6}+sqrt{5}right)^2-dfrac{1}{4}sqrt{120}-sqrt{dfrac{15}{2}}4.left(sqrt{4-sqrt{7}}-sqrt{4+sqrt{7}}right)^25.left(sqrt{sqrt{14}+sqrt{5}}+sqrt{sqrt{14}-sqrt{5}}right)^26.left(sqrt{3}+1right)^3-left(sqrt{3}-1right)^37.left(sqrt{2}+1right)^3-left(sqrt{2}-1right)^38.sqrt{13-sqrt{160}}-sqrt{53+4sqrt{90}}9.sqrt{3-sqrt{5}}+sqrt{3+sqrt{5}}
Đọc tiếp
tính
1.\(\left(\sqrt{15}-2\sqrt{3}\right)^2+12\sqrt{5}\)
2.\(3\sqrt{2}\left(4-\sqrt{2}\right)+3\left(1-2\sqrt{2}\right)^2\)
3.\(\dfrac{1}{2}\left(\sqrt{6}+\sqrt{5}\right)^2-\dfrac{1}{4}\sqrt{120}-\sqrt{\dfrac{15}{2}}\)
4.\(\left(\sqrt{4-\sqrt{7}}-\sqrt{4+\sqrt{7}}\right)^2\)
5.\(\left(\sqrt{\sqrt{14}+\sqrt{5}}+\sqrt{\sqrt{14}-\sqrt{5}}\right)^2\)
6.\(\left(\sqrt{3}+1\right)^3-\left(\sqrt{3}-1\right)^3\)
7.\(\left(\sqrt{2}+1\right)^3-\left(\sqrt{2}-1\right)^3\)
8.\(\sqrt{13-\sqrt{160}}-\sqrt{53+4\sqrt{90}}\)
9.\(\sqrt{3-\sqrt{5}}+\sqrt{3+\sqrt{5}}\)
Rút gọn các biểu thức:
1. sqrt{28}-2sqrt{252}+3sqrt{175}+3sqrt{567}
2. sqrt{left(sqrt{3}+1right)^2}+sqrt{7-4sqrt{3}}
3. sqrt{9-4sqrt{5}}-sqrt{dfrac{8}{7-3sqrt{5}}}
4. dfrac{sqrt{3}}{2-sqrt{3}}+dfrac{2}{2+sqrt{3}}
5. dfrac{2sqrt{2}+1}{1+sqrt{2}}+dfrac{1-2sqrt{2}}{1-sqrt{2}}+left(2-sqrt{3}right).left(2+sqrt{3}right)
6. sqrt{dfrac{2}{3-sqrt{5}}}+sqrt{dfrac{2}{7+sqrt{45}}}
7. dfrac{sqrt{2}}{sqrt{1+sqrt{2}}-1}-dfrac{sqrt{2}}{sqrt{1+sqrt{2}}+1}
8. sqrt{6-2sqrt{5}}+sqrt{dfrac{3-sqrt{5}}{3+sqrt{...
Đọc tiếp
Rút gọn các biểu thức:
1. \(\sqrt{28}-2\sqrt{252}+3\sqrt{175}+3\sqrt{567}\)
2. \(\sqrt{\left(\sqrt{3}+1\right)^2}+\sqrt{7-4\sqrt{3}}\)
3. \(\sqrt{9-4\sqrt{5}}-\sqrt{\dfrac{8}{7-3\sqrt{5}}}\)
4. \(\dfrac{\sqrt{3}}{2-\sqrt{3}}+\dfrac{2}{2+\sqrt{3}}\)
5. \(\dfrac{2\sqrt{2}+1}{1+\sqrt{2}}+\dfrac{1-2\sqrt{2}}{1-\sqrt{2}}+\left(2-\sqrt{3}\right).\left(2+\sqrt{3}\right)\)
6. \(\sqrt{\dfrac{2}{3-\sqrt{5}}}+\sqrt{\dfrac{2}{7+\sqrt{45}}}\)
7. \(\dfrac{\sqrt{2}}{\sqrt{1+\sqrt{2}}-1}-\dfrac{\sqrt{2}}{\sqrt{1+\sqrt{2}}+1}\)
8. \(\sqrt{6-2\sqrt{5}}+\sqrt{\dfrac{3-\sqrt{5}}{3+\sqrt{5}}}-\sqrt{\dfrac{3+\sqrt{5}}{3-\sqrt{5}}}\)
Tính :
a) \(\dfrac{7\sqrt{3}-\:3\sqrt{7}}{\sqrt{7}-\sqrt{3}}+\dfrac{4}{5-\sqrt{21}}-\:\dfrac{6\sqrt{7}}{\sqrt{3}}\)
b) \(\sqrt{\dfrac{2+2\sqrt{3}}{\sqrt{3}-\:1}}+\dfrac{\sqrt{2}}{1+\sqrt{3}}\sqrt{2\:-\sqrt{3}}\)
c) \(\sqrt{2\:-\sqrt{3}}.\:\left(\sqrt{2+\sqrt{3}}+\sqrt{2}\right)\)
1, Rút gọn biểu thức số:
a, (4+\(\sqrt{7}\)) (\(\sqrt{14}-\sqrt{2}\)) \(\sqrt{4-\sqrt{7}}\)
b, \(\dfrac{4+\sqrt{7}}{3\sqrt{2}+\sqrt{4+\sqrt{7}}}\) + \(\dfrac{4-\sqrt{7}}{3\sqrt{2}-\sqrt{4-\sqrt{7}}}\)
tính1.sqrt{147}+sqrt{54}-4sqrt{27}2.sqrt{28}-4sqrt{63}+7sqrt{112}3.sqrt{49}-5sqrt{28}+dfrac{1}{2}sqrt{63}4.left(2sqrt{6}-4sqrt{3}-dfrac{1}{4}sqrt{8}right).3sqrt{6}5.(2sqrt{1dfrac{9}{16}}-5sqrt{5dfrac{1}{16}}):sqrt{16}6.left(sqrt{48}-3sqrt{27}-sqrt{147}right):sqrt{3}7.left(sqrt{50}-3sqrt{49}right):sqrt{2}-sqrt{162}:sqrt{2}8.left(2sqrt{1dfrac{9}{10}}-sqrt{5dfrac{1}{10}}right):sqrt{10}9.2sqrt{dfrac{16}{3}}-3sqrt{dfrac{1}{27}}-6sqrt{dfrac{4}{75}}10.2sqrt{27}-6sqrt{dfrac{4}{3}}+dfrac{3}{5}sqrt{75}11....
Đọc tiếp
tính
1.\(\sqrt{147}+\sqrt{54}-4\sqrt{27}\)
2.\(\sqrt{28}-4\sqrt{63}+7\sqrt{112}\)
3.\(\sqrt{49}-5\sqrt{28}+\dfrac{1}{2}\sqrt{63}\)
4.\(\left(2\sqrt{6}-4\sqrt{3}-\dfrac{1}{4}\sqrt{8}\right).3\sqrt{6}\)
5.(\(2\sqrt{1\dfrac{9}{16}}-5\sqrt{5\dfrac{1}{16}}\)):\(\sqrt{16}\)
6.\(\left(\sqrt{48}-3\sqrt{27}-\sqrt{147}\right):\sqrt{3}\)
7.\(\left(\sqrt{50}-3\sqrt{49}\right):\sqrt{2}-\sqrt{162}:\sqrt{2}\)
8.\(\left(2\sqrt{1\dfrac{9}{10}}-\sqrt{5\dfrac{1}{10}}\right):\sqrt{10}\)
9.\(2\sqrt{\dfrac{16}{3}}-3\sqrt{\dfrac{1}{27}}-6\sqrt{\dfrac{4}{75}}\)
10.\(2\sqrt{27}-6\sqrt{\dfrac{4}{3}}+\dfrac{3}{5}\sqrt{75}\)
11.\(\dfrac{\sqrt{18}}{\sqrt{2}}-\dfrac{\sqrt{12}}{\sqrt{3}}\)
12.\(\dfrac{\sqrt{27}}{\sqrt{3}}+\dfrac{\sqrt{98}}{\sqrt{2}}-\sqrt{175}:\sqrt{7}\)
13.\(\left(\dfrac{\sqrt{8}}{\sqrt{2}}-\dfrac{\sqrt{180}}{\sqrt{5}}\right).\sqrt{5}-\sqrt{\dfrac{81}{11}}.\sqrt{11}\)
14.\(\sqrt{8\sqrt{3}}-2\sqrt{25\sqrt{12}}+4\sqrt{\sqrt{192}}\)
15.\(\left(3\sqrt{2}-2\sqrt{3}\right)\left(3\sqrt{2}+2\sqrt{3}\right)\)
16.\(\left(1+\sqrt{5}-\sqrt{3}\right)\left(1+\sqrt{5}+\sqrt{3}\right)\)