|x + 2017|+|x-2019|=8/[(x-2018).(x-2018)].Tìm x?

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|x + 2017|+|x-2019|=8/[(x-2018).(x-2018)].Tìm x4?

 

Giải:

Nếu x≥0 thì : |x+2017|+|x-2019|≥|x+2017|≥2017

=>

=>

=>1>

=>1>|x-2018|

=>2019>x>2017

xϵS=(2017;2019)/{2018}

dựa vào nhận xét trên ta phá ngoặc trị tuyệt đối:

<=>

<=>

<=>

<=>

<=>

Với x<0: VT=|x+2017|+|x-2019|≥|x-2019|≥2019

VP=

Vậy 2 vế không thể bằng nhau được, nói cách khác là phương trình vô nghiệm.

Vậy ta có 2 nghiệm:

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