\(x^2-x-\frac{3}{4}=0\)
\(\Rightarrow\frac{x^2-x}{1}-\frac{3}{4}=0\)
\(\Rightarrow\frac{\left(x^2-x\right).4}{4}-\frac{3}{4}=0\)
\(\Rightarrow\frac{4x^2-4x-3}{4}=0\)
\(\Rightarrow4x^2-4x-3=0\)
\(\Rightarrow4x^2-6x+2x-3=0\)
\(\Rightarrow2x\left(2x-3\right)+\left(2x-3\right)=0\)
\(\Rightarrow\left(2x+1\right)\left(2x-3\right)=0\)
\(\Rightarrow\orbr{\begin{cases}2x+1=0\\2x-3=0\end{cases}\Rightarrow\orbr{\begin{cases}x=\frac{-1}{2}\\x=\frac{3}{2}\end{cases}}}\)
\(x^2-x-\frac{3}{4}=0\)
<=> \(x^2-x+\frac{1}{4}-1=0\)
<=> \(\left(x-\frac{1}{2}\right)^2-1=0\)
<=> \(\left(x-\frac{1}{2}-1\right)\left(x-\frac{1}{2}+1\right)=0\)
<=> \(\left(x-\frac{3}{2}\right)\left(x+\frac{1}{2}\right)=0\)
làm nốt nhé
