N
nhantd97


CM rằng [TEX]\frac{1}{x}+\frac{1}{y}+\frac{1}{z}=\frac{1}{x+y+z}[/TEX] thì:
[TEX]\frac{1}{x^2003}+\frac{1}{y^2003}+\frac{1}{z^2003}=\frac{1}{x^2003+y^2003+z^2003}[/TEX]
[TEX]\frac{1}{x^2003}+\frac{1}{y^2003}+\frac{1}{z^2003}=\frac{1}{x^2003+y^2003+z^2003}[/TEX]