so sánh các số sau : \(a=\dfrac{35}{49};b=\sqrt{\dfrac{5^2}{7^2}};c=\dfrac{\sqrt{5^2}+\sqrt{35^2}}{\sqrt{7^2}+\sqrt{49^2}};d=\dfrac{\sqrt{5^2}-\sqrt{35^2}}{\sqrt{7^2}-\sqrt{49^2}}\)
so sánh \(\sqrt{4+\sqrt{8}}.\sqrt{2+\sqrt{2}+\sqrt{2}}.\sqrt{2-\sqrt{2}+\sqrt{2}}\)với \(\sqrt{3}\)
Cảm ơn
Rút gọn \(A=\frac{\sqrt{6+2.\left(\sqrt{6}+\sqrt{3}+\sqrt{2}\right)}-\sqrt{6-2.\left(\sqrt{6}-\sqrt{3}+\sqrt{2}\right)}}{\sqrt{2}}\)
Rút gọn\(\sqrt{6+2.\left(\sqrt{6}+\sqrt{3}+\sqrt{2}\right)}-\sqrt{6-2.\left(\sqrt{6}-\sqrt{3}+\sqrt{2}\right)}\)
\(\sqrt{2^2+\sqrt{4}^2+\sqrt{-6}^2+\sqrt{-8}^2}\)
\(\left(\frac{\sqrt{x}+\sqrt{y}}{2\sqrt{x}-2\sqrt{y}}-\frac{2\sqrt{xy}}{x-y}\right).\frac{2\sqrt{x}}{\sqrt{x}-\sqrt{y}}\)
RÚT GỌN
Rút gọn biểu thức: \(P=\frac{3+\sqrt{5}}{\sqrt{2}+\sqrt{3}+\sqrt{5}}-\frac{3-\sqrt{5}}{\sqrt{2}-\sqrt{3}-\sqrt{5}}+\frac{\left(\sqrt{5}-1\right).\sqrt[3]{2+\sqrt{5}}}{\sqrt{28}-10\sqrt{3}+\sqrt{3}}\)
Giúp mk nha!
Tính :\(A=\frac{1}{2\sqrt{1}+1\sqrt{2}}+\frac{1}{3\sqrt{2}+2\sqrt{3}}+\frac{1}{4\sqrt{3}+3\sqrt{4}}+....+\frac{1}{225\sqrt{224}+224\sqrt{225}}\)
Tính:
a) \(\sqrt{\left(-5\right)^2}+\sqrt{5^2}-\sqrt{\left(-3\right)^2}-\sqrt{3^2}-\left(\sqrt{7}\right)^2\)
b) \(\left[\sqrt{4^2}\right]+\sqrt{\left(-4\right)^2}.\left(\sqrt{5}\right)^2-\sqrt{5^{-2}}\)
c) \(\sqrt{\left(-10\right)^2}+10.\left(-\sqrt{5}\right)^2\)
HỘ MK BÀI NÀY NHA MỌI NGƯỜI
Tính \(A=\frac{1}{2.\sqrt{1}+1.\sqrt{2}}+\frac{1}{3\sqrt{2}+2\sqrt{3}}+\frac{1}{4\sqrt{3}+3\sqrt{4}}+....+\frac{1}{100.\sqrt{99}+99.\sqrt{100}}\)