so sánh a= 2020^15+1/2020^16+1 và b=2020^12+1/2020^13+1

0 bình luận về “so sánh a= 2020^15+1/2020^16+1 và b=2020^12+1/2020^13+1”

1. Ta có : A = 2020^15+1/2020^16+1

   => 2020A = 2020^16+2020/2020^16+1 = 2020^16+1+2019/2020^16+1 = 1 + 2019/2020^16+1

   Ta lại có : B = 2020^12+1//2020^13+1

   => 2020B = 2020^13+2020/2020^13+1 = 2020^13+1+2019/2020^13+1 = 1 + 2019/2020^13+1

   Vì 2019/2020^16+1 < 2019/2020^13+1 nên 1 + 2019/2020^16+1 < 1 + 2019/2020^13+1

   => 2020A < 2020B

   => A < B

   Vậy A < B.

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