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#1 2018-07-14 19:44:20

Zeeshan 01
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Registered: 2016-07-22
Posts: 703

Quadratic

Question:  If (3x^2)-2x+4=0  , Then Find α^19  , beta^-3


M.M.Zeeshan.K

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#2 2018-07-15 00:12:13

Alg Num Theory
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Registered: 2017-11-24
Posts: 339
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Re: Quadratic

I presume ɑ and β are the roots, which are complex. Since we are going to deal with their powers, best to convert them to cos–sin form:

So the roots are

one of them is ɑ, the other is β. Since the question doesn’t say which is which, you may as well take your pick. Now use De Moivre’s theorem.

Last edited by Alg Num Theory (2018-07-15 07:08:15)

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