Question

A = 2019 × 2021 – 1                        B  =  2021 × 2023 – 1                      

        ------------------------                                  ----------------------

            2019 × 2021                                           2021 ×  2023

Mình viết hơi khó hiểu một chút mong các b thông cảm ! 

 

 

Answer 1

\(A=\dfrac{2019\times2021-1}{2019\times2021}=\dfrac{2019\times2021}{2019\times2021}-\dfrac{1}{2019\times2021}=1-\dfrac{1}{2019\times2021}\)

\(B=\dfrac{2021\times2023-1}{2021\times2023}=\dfrac{2021\times2023}{2021\times2023}-\dfrac{1}{2021\times2023}=1-\dfrac{1}{2021\times2023}\)