\[x_{1.2}=\frac{-b\pm\sqrt{b^{2}-4ac}}{2a}\]
\( \begin{align}
f \left( x^{2} \right) & \equiv -x+B \) \\
1 -Ax +Bx -1 & \equiv -x+B \\
\left(-A +B \right) x & \equiv -x+B \\
\hline
B & = 0 \\
-A+B & = -1 \\
A & = 1 \\
\hline
2A+B & = 2(1)+0=2
\end{align}\)
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