Tham khảo: https://hoc24.vn/cau-hoi/so-sanh-afrac720131720141va-bfrac720141720151.235038064198
Có A=\(\dfrac{7^{2013}+1}{7^{2014}+1}\)
=>7A=\(\dfrac{7^{2014}+7}{7^{2014}+1}\)
=>7A=\(\dfrac{\left(7^{2014}+1\right)+6}{7^{2014}+1}\)
=>7A=1+\(\dfrac{6}{7^{2014}+1}\)
Tg tự với B ta đc 7B=1+\(\dfrac{6}{7^{2015}+1}\)
Có \(\dfrac{6}{7^{2014}+1}>\dfrac{6}{7^{2015}+1}\)
=>\(1+\dfrac{6}{7^{2014}+1}>1+\dfrac{6}{7^{2015}+1}\)
=>7A > 7B
=>A>B