From previous discussions, we know that an equation of the form
has two roots, but the roots are not always distinct. Take, for example, the equation

We can see that x = –2 when y = 0. This occurs twice, so we call it a double root. It is a single distinct result, but still considered as two roots.
What happens when the equation will not factor over the set of real numbers? Consider
(1) |
From equation (1) it is clear that when
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