a: \(2\sqrt[3]{3}=\sqrt[3]{3\cdot2^3}=\sqrt[3]{24}< \sqrt[3]{54}=3\sqrt[3]{2}\)
b: \(24=2\cdot12=2\cdot\sqrt[3]{1728}< 2\cdot\sqrt[3]{1730}\)
a: \(2\sqrt[3]{3}=\sqrt[3]{3\cdot2^3}=\sqrt[3]{24}< \sqrt[3]{54}=3\sqrt[3]{2}\)
b: \(24=2\cdot12=2\cdot\sqrt[3]{1728}< 2\cdot\sqrt[3]{1730}\)
So sánh 2 số: \(R=\dfrac{3+\sqrt{5}}{2\sqrt{2}+\sqrt{3+\sqrt{5}}}+\dfrac{3-\sqrt{5}}{2\sqrt{2}-\sqrt{3-\sqrt{5}}}\)
\(S=\dfrac{4+\sqrt{7}}{3\sqrt{2}+\sqrt{4+\sqrt{7}}}+\dfrac{4-\sqrt{7}}{2\sqrt{2}-\sqrt{3-\sqrt{5}}}\)
So sánh 2 số: \(R=\dfrac{3+\sqrt{5}}{2\sqrt{2}+\sqrt{3+\sqrt{5}}}+\dfrac{3-\sqrt{5}}{2\sqrt{2}-\sqrt{3-\sqrt{5}}}\)
\(S=\dfrac{4+\sqrt{7}}{3\sqrt{2}+\sqrt{4+\sqrt{7}}}+\dfrac{4-\sqrt{7}}{3\sqrt{2}-\sqrt{4-\sqrt{7}}}\)
Bài 1: Rút gọn biểu thức
a) \(A=\sqrt{26+15\sqrt{3}}\)
b) \(B=\sqrt{4+\sqrt{7}}-\sqrt{4-\sqrt{7}}-\sqrt{2}\)
c) \(C=\sqrt{8-2\sqrt{15}}-\sqrt{8+2\sqrt{15}}\)
d) \(D=\left(\sqrt{6}-2\right)\left(5+\sqrt{24}\right)\sqrt{5-\sqrt{24}}\)
e) \(E=\left(\sqrt{10}-\sqrt{2}\right)\left(\sqrt{3+\sqrt{5}}\right)\)
f) \(F=\sqrt{\sqrt{5}-\sqrt{3-\sqrt{29-12\sqrt{5}}}}\)
g) \(G=\left(2-\sqrt{3}\right)\sqrt{26+15\sqrt{3}}-\left(2+\sqrt{3}\right)\sqrt{26-15\sqrt{3}}\)
h) \(H=\frac{\left(2+\sqrt{3}\right)\sqrt{2-\sqrt{3}}}{\sqrt{2+\sqrt{3}}}\)
So sánh hai số sau:
\(a,2\sqrt{3}\) và \(3\sqrt{2}\)
\(b,\sqrt{24}+\sqrt{45}\) và 12
bài 1:so sánh
a.\(\sqrt{2}+\sqrt{11}và\sqrt{3}+4\)
b.√21-√5 và √20-√6
c.\(\sqrt{24}-1và5\)
so sánh
A = \(\sqrt[3]{2\sqrt{4\sqrt{3}}}\)
B = \(\sqrt[3]{3\sqrt{2\sqrt{3}}}\)
1. So sánh:
a. \(\sqrt{18}+\sqrt{19}\) và 9
b. \(\frac{16}{\sqrt{2}}\)và \(\sqrt{5}.\sqrt{25}\)
2. Cho Hđt \(\sqrt{a\pm\sqrt{b}}=\sqrt{\frac{a+\sqrt{a^2-b}}{2}}\pm\sqrt{\frac{a-\sqrt{a^2-b}}{2}}\)vs \(\left(a,b>0,a^2-b>0\right)\)
Áp dụng kết quả để rút gọn:
a. \(\frac{2+\sqrt{3}}{\sqrt{2}+\sqrt{2+\sqrt{3}}}+\frac{2-\sqrt{3}}{\sqrt{2}-\sqrt{2-\sqrt{3}}}\)
b. \(\frac{\sqrt{3-2\sqrt{2}}}{\sqrt{17-12\sqrt{2}}}-\frac{\sqrt{3+2\sqrt{2}}}{\sqrt{17+12\sqrt{2}}}\)
c. \(\sqrt{\frac{2\sqrt{10}+\sqrt{30}-2\sqrt{2}-\sqrt{6}}{2\sqrt{10}-2\sqrt{2}}}:\frac{2}{\sqrt{3}-1}\)
Tính
\(\sqrt{\frac{3\sqrt{3}-4}{2\sqrt{3}+1}}-\sqrt{\frac{\sqrt{3}+4}{5-2\sqrt{3}}}\)
\(\frac{1}{\sqrt{7-\sqrt{24}+1}}-\frac{1}{\sqrt{7+\sqrt{24}-1}}:\left(\sqrt{3}-\sqrt{2}\right)\)
Rút gọn và tìm điều kiện xác định:
\(\left(\dfrac{\sqrt{a^3}+\sqrt{b^3}}{\sqrt{a}+\sqrt{b}}-\sqrt{ab}\right):\left(a-b\right)+\dfrac{2\sqrt{b}}{\sqrt{a}+\sqrt{b}}\)