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- Đại học Khoa Học Tự Nhiên - ĐHQG TPHCM
![](https://blog.hocmai.vn/wp-content/uploads/2017/07/hot.gif)
![](https://blog.hocmai.vn/wp-content/uploads/2017/07/hot.gif)
Cho tam giacs ABC CMR:
1) [tex]\frac{asinA+bsinB+csinC}{a+b+c}\geqslant \frac{1}{3}\left ( sinA+sinB+sinC \right )[/tex]
2) [tex]\frac{acosA+bcosB+ccosC}{a+b+c}\leqslant \frac{1}{3}\left ( cosA+cosB+cosC \right )[/tex]
1) [tex]\frac{asinA+bsinB+csinC}{a+b+c}\geqslant \frac{1}{3}\left ( sinA+sinB+sinC \right )[/tex]
2) [tex]\frac{acosA+bcosB+ccosC}{a+b+c}\leqslant \frac{1}{3}\left ( cosA+cosB+cosC \right )[/tex]