\(\left(5-2\sqrt{7}\right)^2=53-20\sqrt{7}\)
\(\left(3-\sqrt{10}\right)^2=19-6\sqrt{10}\)
mà \(53-20\sqrt{7}< 19-6\sqrt{10}\)
nên \(5-2\sqrt{7}< 3-\sqrt{10}\)
Rút gọn
\(P=\dfrac{\sqrt[3]{2}+\sqrt{7+2\sqrt{10}}+\sqrt[3]{3\sqrt[3]{4}-3\sqrt[3]{2}-1}}{\sqrt{5}+\sqrt{2}+1}\)
rút gọn
\(\sqrt{3}+\sqrt{11+6\sqrt{ }2}-\sqrt{5}+2\sqrt{6}\)\(\sqrt{2}+\sqrt{6+2\sqrt{ }5}-\sqrt{7+2\sqrt{ }10}\)
\(\sqrt{6+\sqrt{ }6+\sqrt{ }6+\sqrt{ }6........}\)
\(\sqrt{3+\sqrt{ }5+2\sqrt{ }3}+\sqrt{3-\sqrt{ }5+2\sqrt{ }3}\)
\(\sqrt{227-30\sqrt{ }2}+\sqrt{123}+22\sqrt{2}\)
Giải phương trình:
1. \(5x^2+2x+10=7\sqrt{x^4+4}\)
2. \(\dfrac{4}{x}+\sqrt{x-\dfrac{1}{x}}=x+\sqrt{2x-\dfrac{5}{x}}\)
3. \(\sqrt{x^2+2x}=\sqrt{3x^2+4x+1}-\sqrt{3x^2+4x+1}\)
Thực hiện phép tính:
\(A=\dfrac{\sqrt{5+\sqrt{17}}-\sqrt{5-\sqrt{17}}-\sqrt{10-4\sqrt{2}}+4}{\sqrt{3+\sqrt{5}}-\sqrt{3-\sqrt{5}}+2-\sqrt{2}}\)
\(\left\{{}\begin{matrix}3\sqrt{5}x-4y=15-2\sqrt{7}\\-2\sqrt{5}x+8\sqrt{7}y=18\end{matrix}\right.\)
Rút gọn :
a) \(\dfrac{x\sqrt{y}-y\sqrt{x}}{\sqrt{xy}}+\dfrac{x-y}{\sqrt{x}-\sqrt{y}}\)
b) \(\sqrt{\left(\sqrt{5}-1\right).\sqrt{13-\sqrt{69-28\sqrt{5}}}}\)
c) \(\dfrac{\sqrt{3+\sqrt{5}}.\left(\sqrt{6}+\sqrt{2}\right)\left(\sqrt{10}+\sqrt{2}\right)\left(3-\sqrt{5}\right)}{2\sqrt{3+\sqrt{5-\sqrt{13+\sqrt{48}}}}}\)
a)\(\left\{{}\begin{matrix}\sqrt{2}x-\sqrt{3}y=1\\x+\sqrt{3}y=\sqrt{2}\end{matrix}\right.\)
b)\(\left\{{}\begin{matrix}x-2\sqrt{2}y=\sqrt{5}\\\sqrt{2}x+y=1-\sqrt{10}\end{matrix}\right.\)
c)\(\left\{{}\begin{matrix}\left(\sqrt{2}-1\right)x-y=\sqrt{2}\\x+\left(\sqrt{2}+1\right)y=1\end{matrix}\right.\)
d)\(\left\{{}\begin{matrix}\sqrt{3}x-\sqrt{2}y=1\\\sqrt{2}x+\sqrt{3}y=\sqrt{3}\end{matrix}\right.\)
1/Giải phương trình:
a. \(3x+4y=5\sqrt{x^2+y^2}\)
b. \(\dfrac{xy\sqrt{z-5}+xz\sqrt{y-4}+yz\sqrt{x-3}}{xyz}=\dfrac{10\sqrt{3}+15+6\sqrt{5}}{60}\)
c. \(\sqrt{\dfrac{x^2+x+1}{x}}+\sqrt{\dfrac{x}{x^2+x+1}}=\dfrac{2018}{2019}\)
d.\(\sqrt{x+x^2}+\sqrt{x-x^2}=x+1\)
e. \(\dfrac{\sqrt{x-1}}{x}+\dfrac{\sqrt{y-1}}{y}=1\)
2/Giải phương trình:
a.\(\sqrt{x-2}-\sqrt{2x-3}=\dfrac{1-x}{2x-3}\)
b.\(x^2+\dfrac{x^2}{\left(x+1\right)^2}=3\)
Giải hệ phương trình:
\(\left\{{}\begin{matrix}\sqrt{x+5}+\sqrt{y-2}=7\\\sqrt{x-2}+\sqrt{y+5}=7\end{matrix}\right.\)
