Question

tìm x biết x-1/2018+x-3/2019 = x-3/2017

Answer 1

x−1/2019+x−2/2018=x−3/2017+x−4/2016(đề có thiếu không bạn??)

⇔(x−1/2019−1)+(x−2/2018−1)=(x−3/2017−1)+(x−4/2016−1)

⇔x−2020/2019+x−2020/2018=x−2020/2017+x−2020/2016

⇔x−2020/2019+x−2020/2018−x−2020/2017−x−2020/2016

⇔(x−2020)(1/2019+1/2018−1/2017−1/2016)=0

Mà 1/2019+1/2018−1/2017−1/2016≠0

⇔x−2020=0

⇔x=2020