\(\frac{\sqrt{10}-2}{5-\sqrt{10}}\)
\(=\frac{\sqrt2\left(\sqrt5-\sqrt2\right)}{\sqrt5\left(\sqrt5-\sqrt2\right)}\)
\(=\frac{\sqrt2}{\sqrt5}=\frac{\sqrt{10}}{5}\)
\(\frac{\sqrt{10}-2}{5-\sqrt{10}}\)
\(=\frac{\sqrt2\left(\sqrt5-\sqrt2\right)}{\sqrt5\left(\sqrt5-\sqrt2\right)}\)
\(=\frac{\sqrt2}{\sqrt5}=\frac{\sqrt{10}}{5}\)
Rút gọn căn thức :
A = \(\frac{\sqrt{10}+2\sqrt{6}+\sqrt{10}.\sqrt{4+\sqrt{15}}}{\sqrt{2}+\sqrt{3}+\sqrt{5}}\)\(\frac{\sqrt{10}+2\sqrt{6}+\sqrt{10}.\sqrt{4+\sqrt{15}}}{\sqrt{2}+\sqrt{3}+\sqrt{5}}\)
a) Rút gọn biểu thức:
\(P=\frac{5+\sqrt{10}+\sqrt{17}}{2}\left(\frac{5+\sqrt{10}+\sqrt{17}}{2}-5\right)\left(\frac{5+\sqrt{10}+\sqrt{17}}{2}-\sqrt{10}\right)\left(\frac{5+\sqrt{10}+\sqrt{17}}{2}-\sqrt{17}\right).\)
b) Giải phương trình: \(\frac{x+2}{2x-1}+|\frac{4x-2}{x+2}|+1=0\)
rút gọn
\(\frac{2\sqrt{15}-2\sqrt{10}+\sqrt{6}-3}{2\sqrt{5}-2\sqrt{10}-\sqrt{3}+\sqrt{6}}\)
Rút gọn :
A= \(\frac{\sqrt{10}+2\sqrt{6}+\sqrt{10}.\sqrt{4+\sqrt{15}}}{\sqrt{2}+\sqrt{3}+\sqrt{5}}\)
Rút gọn
A= \(\sqrt{4+\sqrt{10+2\sqrt{5}}}+\sqrt{4-\sqrt{10+2\sqrt{5}}}\)
B= \(\frac{1}{1+\sqrt{5}}+\frac{1}{\sqrt{5}+\sqrt{9}}+\frac{1}{\sqrt{9}+\sqrt{13}}+...+\frac{1}{\sqrt{2001}+\sqrt{2005}}\)
rút gọn biểu thức ;
\(p=\frac{3+\sqrt{5}}{\sqrt{10}+\sqrt{3+\sqrt{5}}}-\frac{3-\sqrt{5}}{\sqrt{10}+\sqrt{3-\sqrt{5}}}\)
Rút gọn \(\frac{\sqrt{7-2\sqrt{10}}\left(7+2\sqrt{10}\right)\left(74-22\sqrt{10}\right)}{\sqrt{125}-4\sqrt{50}+5\sqrt{20}+\sqrt{8}}\)
rút gọn Q= ($\frac{\sqrt{x+2} }{x-2\sqrt{x}+4 }$ - $\frac{x-\sqrt{x} }{x\sqrt{x} +8 }$ ). $\frac{5x-10\sqrt{x}+20 }{5\sqrt{x}+4}$
rút gọn biểu thức: P=\(\frac{3+\sqrt{5}}{\sqrt{10}+\sqrt{3+\sqrt{5}}}-\frac{3-\sqrt{5}}{\sqrt{10}+\sqrt{3-\sqrt{5}}}\)
rút gọn biểu thức
\(p=\frac{3+\sqrt{5}}{\sqrt{10}+\sqrt{3+\sqrt{5}}}-\frac{3-\sqrt{5}}{\sqrt{10}+\sqrt{3-\sqrt{5}}}\)