a) \(\sqrt{14-6\sqrt{5}}\)
\(=\sqrt{\left(3\right)^2-2.3.\sqrt{5}+\left(\sqrt{5}\right)^2}\)
\(=\sqrt{\left(3-\sqrt{5}\right)^2}\)
\(=3-\sqrt{5}\)
b) \(\sqrt{46+6\sqrt{5}}=\sqrt{\left(3\sqrt{5}+1\right)^2}=3\sqrt{5}+1\)
a) \(\sqrt{14-6\sqrt{5}}\)
\(=\sqrt{\left(3\right)^2-2.3.\sqrt{5}+\left(\sqrt{5}\right)^2}\)
\(=\sqrt{\left(3-\sqrt{5}\right)^2}\)
\(=3-\sqrt{5}\)
b) \(\sqrt{46+6\sqrt{5}}=\sqrt{\left(3\sqrt{5}+1\right)^2}=3\sqrt{5}+1\)
Rút gọn:
a) \(\sqrt{15-6\sqrt{6}}+\sqrt{33-12\sqrt{6}}\)
b) \(\sqrt{\left(3+\sqrt{5}\right)^2}+\sqrt{14-6\sqrt{5}}\)
c) \(\dfrac{3}{2\sqrt{3}+3}+\dfrac{3}{2\sqrt{3}-3}\)
d) \(\sqrt{\left(\sqrt{3}+4\right)\sqrt{19-8\sqrt{3}}+3}\)
e) \(\dfrac{9-2\sqrt{3}}{3\sqrt{6}-2\sqrt{2}}+\dfrac{3}{3+\sqrt{6}}\)
Rút gọn:
A= \(\sqrt{6-2\sqrt{5}}\) C= \(\sqrt{19-8\sqrt{3}}\)
B = \(\sqrt{4-\sqrt{12}}\) D= \(\sqrt{5-2\sqrt{6}}\)
Rút gọn:
A=\(\left(\dfrac{2\sqrt{3}-\sqrt{6}}{\sqrt{8}-2}-\dfrac{\sqrt{216}}{3}\right).\dfrac{1}{\sqrt{6}}\)
B=\(\sqrt{9+4\sqrt{5}}+\sqrt{9-4\sqrt{5}}\)
rút gọn các câu sau
a,\(2\sqrt{18}-4\sqrt{50}+3\sqrt{32}\)
b,\(\sqrt{\left(\sqrt{8}-4\right)^2}+\sqrt{8}\)
c,\(\sqrt{14-6\sqrt{5}}+\sqrt{6+2\sqrt{5}}\)
1. Tính : \(\dfrac{12}{4-\sqrt{10}}\)-6\(\sqrt{\dfrac{5}{2}}\)+\(\dfrac{5\sqrt{2}+\sqrt{10}}{\sqrt{5}+1}\)
2,Rút gọn:A=(\(\dfrac{\sqrt{x}}{\sqrt{x}-5}\)-\(\dfrac{5}{\sqrt{x}+5}\)+\(\dfrac{10\sqrt{x}}{25-x}\)):\(\dfrac{3}{\sqrt{x}+5}\)
1,Tính \(\dfrac{12}{4-\sqrt{10}}-6\sqrt{\dfrac{5}{2}}+\dfrac{5\sqrt{2}+\sqrt{10}}{\sqrt{5}+1}\)
2,Rút gọn:A=\(\left(\dfrac{\sqrt{x}}{\sqrt{x}-5}-\dfrac{5}{\sqrt{x}+5}+\dfrac{10\sqrt{x}}{25-x}\right):\dfrac{3}{\sqrt{x}+5}\)
Rút gọn:
A=\(\sqrt{6-2\sqrt{5}}-\sqrt{6+2\sqrt{5}}\)
B=\(\sqrt{9+4\sqrt{5}}-\sqrt{9-4\sqrt{5}}\)
C=\(\sqrt{14-6\sqrt{5}-\sqrt{14+6\sqrt{5}}}\)
Rút Gọn:A=\(\frac{2\sqrt{3-\sqrt{3+\sqrt{13+\sqrt{48}}}}}{\sqrt{6}-\sqrt{2}}\)
B=\(\frac{2\sqrt{4-\sqrt{5+\sqrt{21+\sqrt{80}}}}}{\sqrt{10}-\sqrt{2}}\)
C=\(\sqrt{6+2\sqrt{2}\sqrt{3-\sqrt{\sqrt{2}+\sqrt{12}+\sqrt{18-\sqrt{128}}}}}\)
rút gọn
\(\dfrac{\sqrt{15}-\sqrt{6}}{\sqrt{35}-\sqrt{14}}\)
\(\dfrac{\sqrt{15}-\sqrt{5}}{\sqrt{3}-1}\)
\(\dfrac{2\sqrt{8}-\sqrt{12}}{\sqrt{18}-\sqrt{48}}\)