Question

Tìm x thỏa mãn /x-1/ +/1-x/ = 4-x

Answer 1

x-1+1-x=4-x

<=>0=4-x

<=>x-4=0

<=>x=4

Answer 2

+TH1 : x < 1

=> \(\left|x-1\right|+\left|1-x\right|=4-x\)

\(\Leftrightarrow\left|x-1\right|+\left|x-1\right|=4-x\)

\(\Leftrightarrow\left(1-x\right)+\left(1-x\right)=4-x\) ( do x < 1 nên \(\left|x-1\right|=1-x\) )

\(\Leftrightarrow2-2x=4-x\)

\(\Leftrightarrow-x=2\Leftrightarrow x=-2\)

+ TH2 : \(x\ge1\)

\(\Rightarrow\left|x-1\right|+\left|x-1\right|=4-x\)

\(\Leftrightarrow x-1+x-1=4-x\)

\(\Leftrightarrow2x-2=4-x\)

\(\Leftrightarrow3x=6\Leftrightarrow x=2\)