I'm having trouble with the following equation. I get four real zeros (+-5, +-2), but that would leave three imaginary zeros, which I thought always came in congugate pairs. x^7+5*x^6-20*x^5-139*x^4-161*x^3+326*x^2+900*x+600

Question

I'm having trouble with the following equation.  I get four real zeros (+-5, +-2), but that would leave three imaginary zeros, which I thought always came in congugate pairs.   x^​7+​5*​x^​6-​20*​x^​5-​139*​x^​4-​161*​x^​3+​326*​x^​2+​900*​x+​600

rsadhvika · Answer

one of them must be a repeated zero, like (x+2)(x+2)

anonymous · Answer

Thanks, but how would I know that?  Would it show up in graphing?  (it doesn't seem to)

rsadhvika · Answer

I think graph just touches the x-axis, when u have a repeated root

rsadhvika · Answer

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rsadhvika · Answer

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