m = “2^2019 – (2^2018 + 2^2017 + 2^2016 + …. + 2^1 + 3)”
CẦU LÀM NHANH TRONG 5′ Ạ!!!!!!!!!!!
m = “2^2019 – (2^2018 + 2^2017 + 2^2016 + …. + 2^1 + 3)” CẦU LÀM NHANH TRONG 5′ Ạ!!!!!!!!!!!
By Amara
By Amara
m = “2^2019 – (2^2018 + 2^2017 + 2^2016 + …. + 2^1 + 3)”
CẦU LÀM NHANH TRONG 5′ Ạ!!!!!!!!!!!
`M = 2^2019 – (2^2018 + 2^2017 + … + 2^1 + 3 )`
`=> M= 2^2019 – 2^2018 – 2^2017 – … – 2^1 -3`
`=> 2M = 2(2^2019 – 2^2018 – 2^2017 – …. – 2^2 – 3 )`
`=> 2M = 2^2020 – 2^2019 – 2^2018 – … – 2^3 – 6`
`=> 2M – M = ( 2^2020 – 2^2019 – 2^2018 – … – 2^2 – 6) – (2^2019 – 2^2018 – 2^2017 – … – 2^1-3)`
`=> M = 2^2020 – 2^2019 – 2^2018 – … – 2^3 – 6 – 2^2019 + 2^2018 + 2^2017 + … + 2^2 + 3`
`=> M = 2^2020 – 2^2019 – 2^2019 – 6 +3 + 2`
`=> M = 2^2019 . 2 – 2^2019 – 2^2019 – 6 +3 +2`
`=> M = 2^2019 ( 2 – 1) – 2^2019 -1`
`=> M = 2^2019 – 2^2019 – 1`
`=> M = -1`
Đáp án + Giải thích các bước giải:
`M = 2^2019 – (2^2018 + 2^2017 + 2^2016 + …. + 2^1 + 3)`
`=>M = 2^2019 – 2^2018 – 2^2017 – 2^2016 – …. – 2^1 – 3`
`=> 2M = 2^2020 – 2^2019 – 2^2018 – 2^2017 – …. – 2^2 – 6`
`=> 2M-M = 2^2020 – 2^2019 – 2^2018 – 2^2017 – …. – 2^2 – 6 – 2^2019 + 2^2018 + 2^2017 + 2^2016 + …. + 2^1 + 3`
`=> M = 2^2020 – 2^2019 – 2^2019 + 2 + 3 – 6 `
`=> M = 2^2020 – 2^2020 – 1`
`=> M = – 1`