H
hoabattu_94


Bài 1 ( vòng 2)
2)CMR
[TEX]\frac{1}{4+a^4}+\frac{3}{4+3^4}+.....+\frac{2n-1}{4+(2n-1)^4}=\frac{n^2}{4n^2+1}[/TEX]
2)CMR
[TEX]\frac{1}{4+a^4}+\frac{3}{4+3^4}+.....+\frac{2n-1}{4+(2n-1)^4}=\frac{n^2}{4n^2+1}[/TEX]