e, \(4x^2-12x+5=0\)
\(\Rightarrow4x^2-10x-2x+5=0\)
\(\Rightarrow\left(4x^2-10x\right)-\left(2x-5\right)=0\)
\(\Rightarrow2x.\left(2x-5\right)-\left(2x-5\right)=0\)
\(\Rightarrow\left(2x-5\right).\left(2x-1\right)=0\)
\(\Rightarrow\left\{{}\begin{matrix}2x-5=0\\2x-1=0\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}2x=5\\2x=1\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=2,5\\x=0,5\end{matrix}\right.\)
Vậy-..
f, \(2x^2+5x+3=0\)
\(\Rightarrow2x^2+3x+2x+3=0\)
\(\Rightarrow\left(2x^2+3x\right)+\left(2x+3\right)=0\)
\(\Rightarrow x.\left(2x+3\right)+\left(2x+3\right)=0\)
\(\Rightarrow\left(2x+3\right).\left(x+1\right)=0\)
\(\Rightarrow\left\{{}\begin{matrix}2x+3=0\\x+1=0\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}2x=-3\\x=-1\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=\dfrac{-3}{2}\\x=-1\end{matrix}\right.\)
Vậy-.
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