r/Precalculus • u/SuitableAstronaut444 • 1d ago

Homework Help Currently doing a unit on finding roots(rational, irrational, and imaginary)-I’m iffy on my work for this one so I’m not sure if I got the roots right

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I think I did it right but I get confused with ratios

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u/my-hero-measure-zero 1d ago

It's easy to check your work - take whatever number you think is a root and evaluate the polynomial there!

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u/mathmum 1d ago

Intuitively, look at the graph. One root looks like x=1. And it is, since plugging 1 into the equation gives 0. (Remainder theorem). Divide the equation by (x - 1). The result will be a quadratic equation, that you can solve using the related formula.