\(\sqrt{7-2\sqrt{12}}=\sqrt{\left(2-\sqrt{3}\right)^2}=\left|2-\sqrt{3}\right|=2-\sqrt{3}\)
=> Chọn C
\(\sqrt{7-2\sqrt{12}}=\sqrt{\left(2-\sqrt{3}\right)^2}=\left|2-\sqrt{3}\right|=2-\sqrt{3}\)
=> Chọn C
thực hiện phép tính
a)\(3\sqrt{9-\sqrt{25}+2\sqrt{49}}\)
b)\(7\sqrt[3]{27}-\sqrt[3]{64}+2\sqrt[3]{8}\)
c)\(\left(\sqrt{28}+2\sqrt{14}+3\sqrt{7}\right)\left(\sqrt{7}-7\sqrt{8}\right)\)
d)\(\frac{6\sqrt{7}+\sqrt{12}}{2}+\sqrt{7}+\sqrt{67-12\sqrt{7}}\)
\(A=\sqrt{12-3\sqrt{7}}-\sqrt{12+3\sqrt{7}}\)
\(B=\sqrt{4+\sqrt{10+2\sqrt{5}}}+\sqrt{4-\sqrt{10+2\sqrt{5}}}\)\(C=\sqrt{3-\sqrt{5}}+\sqrt{3+\sqrt{5}}\)
* Thực hiện phép tính
a, A= \(\sqrt{12-3\sqrt{7}}-\sqrt{12+3\sqrt{7}}\)
b, B= \(\sqrt{4+\sqrt{10+2\sqrt{5}}}+\sqrt{4-\sqrt{10+2\sqrt{5}}}\)
c, C= \(\sqrt{3-\sqrt{5}}+\sqrt{3+\sqrt{5}}\)
Rút gọn các biểu thức sau
a) \(\dfrac{1}{\sqrt{3}}+\dfrac{1}{3\sqrt{2}}+\dfrac{1}{\sqrt{3}}\dfrac{\sqrt{3}-\sqrt{2}}{2\sqrt{3}}\) b) \(\sqrt{12-3\sqrt{7}}-\sqrt{12+3\sqrt{7}}\) c) \(\sqrt[3]{\dfrac{3}{4}}.\sqrt[3]{\dfrac{9}{16}}\)
d) \(\dfrac{\sqrt[3]{54}}{\sqrt[3]{-2}}\) e) \(\sqrt[3]{5\sqrt{2}+7}-\sqrt[3]{5\sqrt{2}-7}\)
Thực hiện các phép tính sau:
a, A=\(\sqrt{12-3\sqrt{7}}-\sqrt{12+3\sqrt{7}}\)
b, B=\(\sqrt{4+\sqrt{10+2\sqrt{5}}}+\sqrt{4-\sqrt{10+2\sqrt{5}}}\)
c, C=\(\sqrt{3-\sqrt{5}}+\sqrt{3+\sqrt{5}}\)
tính
a, \(A=2\sqrt{12}-3\sqrt{48}+4\sqrt{75}\)
\(B=\sqrt{\frac{4-\sqrt{7}}{4+\sqrt{7}}}+\sqrt{\frac{4+\sqrt{7}}{4-\sqrt{7}}}\)
c, \(C=\frac{3-2\sqrt{3}}{\sqrt{3}}+\frac{6}{3+\sqrt{3}}\)
d,
a,\(\sqrt{8+2\sqrt{15}}\) -\(\sqrt{6+2\sqrt{15}}\)
b, \(\sqrt{17-2\sqrt{72}}-\sqrt{19+2\sqrt{18}}\)
c, \(\sqrt{8-2\sqrt{7}}+\sqrt{8+2\sqrt{7}}\)
d, \(\sqrt{12+2\sqrt{11}}-\sqrt{12-2\sqrt{11}}\)
e, \(\sqrt{10-2\sqrt{21}}-\sqrt{9-2\sqrt{14}}\)
tính
A=\(\left(1-\sqrt{7}\right).\dfrac{\sqrt{7}+7}{2\sqrt{7}}\)
B=\(3\sqrt{3}+4\sqrt{12}-5\sqrt{27}\)
C=\(\sqrt{32}-\sqrt{50}+\sqrt{18}\)
D=\(\sqrt{72}+\sqrt{4\dfrac{1}{2}}-\sqrt{32}-\sqrt{162}\)
E=\(\dfrac{1}{2}\sqrt{48}-2\sqrt{75}-\dfrac{\sqrt{33}}{\sqrt{11}}+5\sqrt{1\dfrac{1}{3}}\)
Rút gọn biểu thức
a. A = \(\sqrt{11-6\sqrt{2}}+3+\sqrt{2}\)
b. B = \(\sqrt{29-4\sqrt{7}}+\sqrt{23+8\sqrt{7}}\)
c. C = \(\sqrt{12+2\sqrt{11}+\sqrt{12-2\sqrt{11}}}\)
d. D = \(\left(3-\sqrt{2}\right).\sqrt{11+6\sqrt{2}}\)