\(\left|2x-1\right|< 5\)
\(\Leftrightarrow-5< 2x-1< 5\)
\(\Leftrightarrow-4< 2x< 6\)
\(\Leftrightarrow-2< x< 3\)
Vậy.....
\(|2x-1|<5 \\ \Leftrightarrow \begin{cases} 2x-1<5 \\ 2x-1 >-5 \\ \end{cases} \\ \Leftrightarrow \begin{cases} 2x<6 \\ 2x>-4 \\ \end{cases} \\ \Leftrightarrow \begin{cases} x<3 \\ x>-2 \\ \end{cases} \\ \Leftrightarrow x \in \{-1;0;1;2\}\)
|2x - 1| < 5
\(\Rightarrow\) \(\left\{{}\begin{matrix}2x-1< 5\\2x-1>-5\end{matrix}\right.\)
\(\Rightarrow\) \(\left\{{}\begin{matrix}2x< 6\\2x>-4\end{matrix}\right.\)
\(\Rightarrow\) \(\left\{{}\begin{matrix}x< 3\\x>-2\end{matrix}\right.\)
\(\Rightarrow\) -2 < x < 3
Mà x \(\in\) N
\(\Rightarrow\) x \(\in\) {0; 1; 2}
Vậy x = 0; x = 1; x = 2
Chúc bn học tốt!
Ta có: |2x-1|<5
\(\Leftrightarrow\left|2x-1\right|\in\left\{0;1;2;3;4\right\}\)
\(\Leftrightarrow2x-1\in\left\{0;1;-1;2;-2;3;-3;4;-4\right\}\)
\(\Leftrightarrow2x\in\left\{1;2;0;3;-1;4;-2;5;-3\right\}\)
\(\Leftrightarrow x\in\left\{\dfrac{1}{2};1;0;\dfrac{3}{2};-\dfrac{1}{2};2;-1;5;-\dfrac{3}{2}\right\}\)
mà x là số tự nhiên
nên \(x\in\left\{0;1;2\right\}\)
Vậy: \(x\in\left\{0;1;2\right\}\)
