Question

So sánh 
A = 2021/2022 + 2022/2023 + 2023/2024 + 2024/2021 và B = 4 
 

Answer 1

Lời giải:

\(A-4=(\frac{2021}{2022}-1)+(\frac{2022}{2023}-1)+(\frac{2023}{2024}-1)+(\frac{2024}{2021}-1)\\ =\frac{3}{2021}-\frac{1}{2022}-\frac{1}{2023}-\frac{1}{2024}\\ =(\frac{1}{2021}-\frac{1}{2022})+(\frac{1}{2021}-\frac{1}{2023})+(\frac{1}{2021}-\frac{1}{2024})>0\)

$\Rightarrow A>4$