So sánh ( Không sử dụng máy tính)
a) \(\sqrt{2}+\sqrt{3}\) và 3
b) 5 - và\(3\sqrt{2}-2\)
c) 3+ và \(2\sqrt{2}+6\)
Rút gọn
a)
A= \(\sqrt {a - 2 - 2\sqrt {a-3}} - \sqrt {a+1-4\sqrt {a-3}} (3<=a<=4)\)\(B= \sqrt {\sqrt 5 -\sqrt{3 - \sqrt{29 - 12\sqrt 5}}} × \sqrt{2003-2\sqrt{2005-2\sqrt2004}}\)
So sánh:
a, 5+\(\sqrt{ }\)2 và 4+ \(\sqrt{ }\)3
b, \(\)\(\sqrt{ }\)8 - \(\sqrt{ }\)2 và \(\sqrt{ }\)5 - \(\sqrt{ }\)3
c, \(\sqrt{ }\)5 - \(\sqrt{ }\)3 và \(\sqrt{ }\)10 - \(\sqrt{ }\)7
So sánh \(3\sqrt{5}\) và \(2\sqrt{10}\)
so sánh
2 và \(\sqrt{2}\)+ 1
2\(\sqrt{31}\)và 10
\(-3\sqrt{11}\)và - \(\sqrt{12}\)
So sánh \(\sqrt{3+\sqrt{20}}\) và \(\sqrt{5+\sqrt{5}}\)
Thực hiện các phép tính sau:
a)\(\frac{10+2\sqrt{10}}{\sqrt{5}+\sqrt{2}}+\frac{8}{1-\sqrt{5}}\)
b) \(\frac{2\sqrt{8}-\sqrt{12}}{\sqrt{18}-\sqrt{48}}-\frac{\sqrt{5}+\sqrt{27}}{\sqrt{30}+\sqrt{162}}\)
c) \(\sqrt{\frac{2-\sqrt{3}}{2+\sqrt{3}}}+\sqrt{\frac{2+\sqrt{3}}{2-\sqrt{3}}}\)
d) \(\frac{\sqrt{3-\sqrt{5}}.\left(3+\sqrt{5}\right)}{\sqrt{10}+\sqrt{2}}\)
e) \(\frac{1}{\sqrt{2}+\sqrt{2+\sqrt{3}}}+\frac{1}{\sqrt{2}-\sqrt{2-\sqrt{3}}}\)
f) \(\frac{\left(\sqrt{5}+2\right)^2-8\sqrt{5}}{2\sqrt{5}-4}\)
tính
a/ (\(\sqrt{2006}\)- \(\sqrt{2005}\)).(\(\sqrt{2006}\)+ \(\sqrt{2005}\))
b/ (\(\frac{1}{7-4\sqrt{3}}\)+ \(\frac{2}{7+4\sqrt{3}}\)).(21+4\(\sqrt{3}\))
c/ \(3\sqrt{\frac{9}{8}}\)- \(\sqrt{\frac{49}{2}}\)+ \(\sqrt{\frac{25}{18}}\)
d/ ( \(5\sqrt{28}-2\sqrt{63}+3\sqrt{112}\)) : \(\sqrt{7}\)
e/ \(\left(\sqrt{5}+\sqrt{3}\right)\sqrt{8-2\sqrt{15}}\)
f/ (\(\frac{4\sqrt{21}-4\sqrt{15}-\sqrt{14}+\sqrt{10}}{4\sqrt{6}-2+4\sqrt{15}-\sqrt{10}}\)
tính
a/ (\(\sqrt{2006}\)- \(\sqrt{2005}\)).(\(\sqrt{2006}\)+ \(\sqrt{2005}\))
b/ (\(\frac{1}{7-4\sqrt{3}}\)+ \(\frac{2}{7+4\sqrt{3}}\)).(21+4\(\sqrt{3}\))
c/ \(3\sqrt{\frac{9}{8}}\)- \(\sqrt{\frac{49}{2}}\)+ \(\sqrt{\frac{25}{18}}\)
d/ ( \(5\sqrt{28}-2\sqrt{63}+3\sqrt{112}\)) : \(\sqrt{7}\)
e/ \(\left(\sqrt{5}+\sqrt{3}\right)\sqrt{8-2\sqrt{15}}\)
f/ (\(\frac{4\sqrt{21}-4\sqrt{15}-\sqrt{14}+\sqrt{10}}{4\sqrt{6}-2+4\sqrt{15}-\sqrt{10}}\)