Question

Tim x ∈ Z bt:

\(|2x-1|=5\)

Answer 1

|2x-1|=5

=> 2x-1=5 hoặc 2x-1=-5

+, 2x-1=5

2x=5+1

2x=6

x=6:2

x=3

+, 2x-1=-5

2x=-5+1

2x=-4

x=(-4):2

x=-2

Vậy x ∈ {3;-2}

Answer 2

|2x-1|=5

\(\Rightarrow\)\(\left[{}\begin{matrix}2x-1=5\\2x-1=-5\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=\left(5+1\right):2=3\\x=\left(-5+1\right):2=-2\end{matrix}\right.\)

Vậy: \(\left[{}\begin{matrix}x=3\\x=-2\end{matrix}\right.\)

Answer 3

{ 3 , -2 }