Ta có:
\(\frac{1}{3}\)A = \(\frac{3^{10}+1}{3^{10}+3}\)
= \(\frac{3^{10}+1}{3^{10}+1+2}\)
= \(1+\frac{3^{10}+1}{2}\)
\(\frac{1}{3}\)B = \(\frac{3^9+1}{3^9+3}\)
= \(\frac{3^9+1}{3^9+1+2}\)
= 1 + \(\frac{3^9+1}{2}\)
Đương nhiên \(1+\frac{3^{10}+1}{2}\) > 1 + \(\frac{3^9+1}{2}\)
=> A > B