\(\sqrt{30+12\sqrt{6}}-\sqrt{21-6\sqrt{6}}=\sqrt{12+2.\sqrt{12}.\sqrt{18}+18}-\sqrt{18-2.\sqrt{18}.\sqrt{3}+3}\)
\(=\sqrt{12+2.\sqrt{12}.\sqrt{18}+18}-\sqrt{18-2.\sqrt{18}.\sqrt{3}+3}\)
\(=\sqrt{\left(\sqrt{12}+\sqrt{18}\right)^2}-\sqrt{\left(\sqrt{18}-\sqrt{3}\right)^2}\)
\(=\sqrt{12}+\sqrt{18}-\sqrt{18}+\sqrt{3}=\sqrt{12}+\sqrt{3}\)
\(\left(\sqrt{6}-\sqrt{5}\right)^2-\sqrt{11+2\sqrt{30}}\)
\(\sqrt{8+2\sqrt{15}}-\sqrt{8-2\sqrt{15}}\)
\(\sqrt{11+4\sqrt{7}}-\sqrt{14-6\sqrt{5}}\)
\(\sqrt{22-12\sqrt{2}}-\sqrt{19+6\sqrt{2}}\)
\(\sqrt{-6\sqrt{3}+12}+\sqrt{-12\sqrt{3}+21}\)
1. Rút gọn các biểu thức sau:
E = \(\sqrt{37-6\sqrt{30}}\)
F = \(\sqrt{51-6\sqrt{30}}\)
G = \(\sqrt{59-6\sqrt{30}}\)
H = \(\sqrt{17-2\sqrt{30}}\)
Tính:
a) \(\dfrac{6}{\sqrt{2}-\sqrt{3}+3}\)
b) \(\dfrac{1}{\sqrt{10}+\sqrt{15}+\sqrt{14}+\sqrt{21}}\)
c)\(\dfrac{1}{2+\sqrt{5}+2\sqrt{2}+\sqrt{10}}\)
d)\(\dfrac{2\sqrt{30}}{\sqrt{5}+\sqrt{6}+\sqrt{7}}\)
rút gọn
\(\sqrt{x+12+6\sqrt{x+3}}-\sqrt{x+12-6\sqrt{x+3}}\) ( x>6)
A=\(\sqrt{19-3\sqrt{ }40}\)-\(\sqrt{19+3\sqrt{ }40}\)
B=\(\sqrt{21-6\sqrt{ }6}\) +\(\sqrt{9+2\sqrt{ }18}\) -2\(\sqrt{6+3\sqrt{ }3}\)
C=\(\sqrt{6+2\sqrt{ }2\sqrt{ }3-\sqrt{ }4+2\sqrt{ }3}\)
D=\(\sqrt{4+\sqrt{ }15}\)-\(\sqrt{7-3\sqrt{ }5}\)
E=\(\sqrt{2+\sqrt{ }3}\)+\(\sqrt{2-\sqrt{ }3}\)
F=\(\sqrt{12-3\sqrt{ }7}\)-\(\sqrt{12+3\sqrt{ }7}\)
G=(3\(\sqrt{2}\)+\(\sqrt{6}\)).\(\sqrt{6-3\sqrt{ }3}\)
H=\(\sqrt{9-4\sqrt{ }5}-\sqrt{14-6\sqrt{ }5}\)
I=\(\sqrt{9-4\sqrt{ }2}\)-\(\sqrt{13-4\sqrt{ }3}\)
Rút gọn căn bậc hai theo hằng đẳng thức:
a)\(\left(4\sqrt{2}+\sqrt{30}\right).\left(\sqrt{5}-\sqrt{3}\right)\sqrt{4-\sqrt{15}}\)
b)\(2.\left(\sqrt{10}-\sqrt{2}\right).\left(4+\sqrt{6-2\sqrt{5}}\right)\)
c)\(\left(7+\sqrt{14}\right).\sqrt{9-2\sqrt{14}}\)
d)\(\sqrt{\dfrac{289+4\sqrt{72}}{16}}\)
e) \(\left(\sqrt{21}+7\right).\sqrt{10-2\sqrt{21}}\)
f)\(\sqrt{2-\sqrt{3}.\left(\sqrt{6}+\sqrt{2}\right)}\)
g) \(\sqrt{2}\sqrt{8+3\sqrt{7}}\)
h) \(\sqrt{11+6\sqrt{2}}\)
a,\(\left(\sqrt{27}-\sqrt{12}-\sqrt{108}-\sqrt{192}\right):\sqrt{3}\)
b,\(\frac{\sqrt{2}-\sqrt{6}}{1-\sqrt{3}}\frac{3+2\sqrt{7}}{1+\sqrt{3}}\)
c,(\(\sqrt{15-6\sqrt{6}}+\sqrt{33-12\sqrt{6}}\)
Gỉai giúp mk vs
\(\sqrt{21-6\sqrt{6}}\)
\(\sqrt{14-6\sqrt{5}}+\sqrt{14+6\sqrt{5}}\)
\(\left(3-\sqrt{2}\right)\sqrt{7+4\sqrt{3}}\)
\(\sqrt{13+4\sqrt{10}}+\sqrt{13-4\sqrt{10}}\)
\(\sqrt{6}\left(\sqrt{26+15\sqrt{3}}+\sqrt{26-15\sqrt{3}}\right)\)
Tính \(C=\sqrt{13+30\sqrt{2+\sqrt{9+4\sqrt{2}}}}\)
Tính\(D=\sqrt{6+2\sqrt{5-\sqrt{29-12\sqrt{5}}}}\)
Bài 1:
1.\(\sqrt{2-\sqrt{3}}\)
2.\(\sqrt{3+\sqrt{5}}\)
3.\(\sqrt{21-6\sqrt{6}}\)
4.\(\sqrt{5+2\sqrt{6}}-\sqrt{5-2\sqrt{6}}\)
5.\(\left(2-\sqrt{3}\right)\sqrt{7+4\sqrt{3}}\)
6.\(\sqrt{13+4\sqrt{10}}+\sqrt{13-4\sqrt{10}}\)
