Bunuel wrote:
If a·b≠0, and (x+a)(x+b)=0, is x=a?
a·b≠0 implies that none of them is0.
\((x+a)(x+b)=0\) -->\(x=-a\) or\(x=-b\) .
(1) x−b=0 -->\(x=b\) . Since b is not 0, then x cannot be b and -b simultaneously (x=b and x=-b would mean that b=-b --> b=0), hence\(x\neq{-b}\) . So,\(x=-a\) . The question asks whether\(x=a\) : again since a is not 0, then x cannot be a and -a simultaneously, hence\(x\neq{a}\) . We have a NO answer to the question. Sufficient.
(2) a=−b -->\(x=-a\) or\(x=-b=a\) . So, x may
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