Question

Giải hộ mik với 

Answer 1

Lời giải:

\(\frac{2019\times 2022-19}{2020\times 2021-21}=\frac{(2020-1)\times 2022-19}{2020\times 2021-21}=\frac{2020\times 2022-2022-19}{2020\times 2021-21}\)

\(=\frac{2020\times (2021+1)-2022-19}{2020\times 2021-21}=\frac{2021\times 2021+2020-2022-19}{2020\times 2021-21}=\frac{2020\times 2021-21}{2020\times 2021-21}=1\)