So sánh: 2020^2019 + 2020^2020 và 2021^2020. 09/07/2021 Bởi Rose So sánh: 2020^2019 + 2020^2020 và 2021^2020.
`2020^2019+2020^2020=2020^2019 . (1+2020)=2021 . 2020^2019` `2021^2020=2021 . 2021^2019` Do `0<2020<2021` `=> 2021 . 2020^2019<2021 . 2021^2019` `=> 2020^2019+2020^2020<2021^2020` Bình luận
Đáp án: $2021^{2020} > 2020^{2019} + 2020^{2020}$ Giải thích các bước giải: $+) \quad 2020^{2019} + 2020^{2020}$ $= 2020^{2019} + 2020^{2019}.2020$ $= 2020^{2019}.2021$ $+) \quad 2021^{2020}$ $= 2021^{2019}.2021$ Do $2021 > 2020$ $\to 2021^{2019} > 2020^{2019}$ $\to 2021^{2019}.2021 > 2020^{2019}.2021$ $\to 2021^{2020} > 2020^{2019} + 2020^{2020}$ Bình luận
`2020^2019+2020^2020=2020^2019 . (1+2020)=2021 . 2020^2019`
`2021^2020=2021 . 2021^2019`
Do `0<2020<2021`
`=> 2021 . 2020^2019<2021 . 2021^2019`
`=> 2020^2019+2020^2020<2021^2020`
Đáp án:
$2021^{2020} > 2020^{2019} + 2020^{2020}$
Giải thích các bước giải:
$+) \quad 2020^{2019} + 2020^{2020}$
$= 2020^{2019} + 2020^{2019}.2020$
$= 2020^{2019}.2021$
$+) \quad 2021^{2020}$
$= 2021^{2019}.2021$
Do $2021 > 2020$
$\to 2021^{2019} > 2020^{2019}$
$\to 2021^{2019}.2021 > 2020^{2019}.2021$
$\to 2021^{2020} > 2020^{2019} + 2020^{2020}$