Question

Answer 1

a.

\(x^2-4=0\\ \Leftrightarrow x^2=4\\ \Leftrightarrow x=\pm2.\)

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b.

. \(2x^2-x=0\\ \Leftrightarrow x\left(2x-1\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=0\\2x-1=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=0\\2x=1\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=0\\x=\dfrac{1}{2}\end{matrix}\right.\)

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Answer 2

error tí

\(2x^2-x=0\\ \Leftrightarrow x\left(2x-1\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=0\\2x-1=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=0\\2x=1\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=0\\x=\dfrac{1}{2}\end{matrix}\right.\)

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