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nguyenphucthucuyen


Cho a,b,c là các số thực dương thỏa : ab + bc + ca =3 . CMR:
[TEX]\frac{a}{2a^2 + bc} + \frac{b}{2b^2 +ca} + \frac{c}{2c^2+ab}[/TEX]\geqabc
........................................THANK^^..............................................................................
[TEX]\frac{a}{2a^2 + bc} + \frac{b}{2b^2 +ca} + \frac{c}{2c^2+ab}[/TEX]\geqabc
........................................THANK^^..............................................................................