`b) |x - 3| - |x^2 - 1| = 0`
`-> |x - 3| = |x^2 - 1|`
`->` \(\left[ \begin{array}{l}x - 3 = x^2 - 1\\x - 3 = 1 - x^2\end{array} \right.\)
`->` \(\left[ \begin{array}{l}x^2 - x + 2 = 0 (l)\\x^2 + x - 4 = 0\end{array} \right.\)
`->` \(\left[ \begin{array}{l}x = \dfrac{\sqrt{17} - 1}{2}\\x = \dfrac{-\sqrt{17} - 1}{2}\end{array} \right.\)
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