a: Ta có: \(x^2-5< 2\)
\(\Leftrightarrow x^2< 7\)
\(\Leftrightarrow-\sqrt{7}< x< \sqrt{7}\)
b: Ta có: \(\left|x\right|< 3\)
\(\Leftrightarrow-3< x< 3\)
c: Ta có: \(4-x^2\le0\)
\(\Leftrightarrow x^2\ge4\)
\(\Leftrightarrow\left[{}\begin{matrix}x\ge2\\x\le-2\end{matrix}\right.\)
d: Ta có: \(\left|2x-1\right|>0\)
\(\Leftrightarrow2x-1\ne0\)
\(\Leftrightarrow x\ne\dfrac{1}{2}\)
e: Ta có: \(4x^2-4x+1>0\)
\(\Leftrightarrow\left(2x-1\right)^2>0\)
\(\Leftrightarrow2x-1\ne0\)
hay \(x\ne\dfrac{1}{2}\)
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