\(x^2-x^2-2x-1-2=0\)
\(-2x-3=0\Leftrightarrow x=\dfrac{-2}{3}\)
\(\left(x-2x+1\right)\left(x+2x-1\right)=0\)
\(\left[{}\begin{matrix}-x+1=0\\3x-1=0\end{matrix}\right.\)\(\Leftrightarrow\left[{}\begin{matrix}x=1\\x=\dfrac{1}{3}\end{matrix}\right.\)
a)\(x^2-x\left(x+2\right)-1=2\\ \Rightarrow x^2-x^2-2x-1=2\\ \Rightarrow-2x=3\\ \Rightarrow x=-\dfrac{3}{2}\)
b) \(x^2=\left(2x-1\right)^2\\ \Rightarrow\left[{}\begin{matrix}x=2x-1\\x=1-2x\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=1\\x=\dfrac{1}{3}\end{matrix}\right.\)
a. x2 - x(x + 2) - 1 = 2
<=> x2 - x2 - 2x = 3
<=> -2x = 3
<=> \(x=-\dfrac{3}{2}\)
b. x2 = (2x - 1)2
<=> x2 - (2x - 1)2 = 0
<=> (x - 2x + 1)(x + 2x - 1) = 0
<=> (1 - x)(3x - 1) = 0
<=> \(\left[{}\begin{matrix}1-x=0\\3x-1=0\end{matrix}\right.\)
<=> \(\left[{}\begin{matrix}x=1\\x=\dfrac{1}{3}\end{matrix}\right.\)
