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Complex Numbers Question (2 Viewers)

nrlwinner

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Using Doivire's Theorem, find the cube roots of 8.

How would I do that?
 

nrlwinner

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Thanks for all the help guys. One more quick thing. Can someone help me prove this.



PS. That 1/z is meant to be 1/z^n
 

nrlwinner

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Another question here.

If

show that the roots of the equation



are

 

tommykins

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...get a textbook and learn it yourself.
it's all fine and dandy that we're helping you but at least show SOME effort as to what progress you've made.
 

addikaye03

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Another question here.

If

show that the roots of the equation



are

Just let a, b, and c be the roots of the equation

therefore a+b+c=-b/a

ab+ac+bc=c/a

abc=-d/a

then resubstitute for x, doesn't require much complex knowledge at all if you attack it like that.

Complex number way: x=cos^2x, Let 4@= 32x^3-48^2+18x-1 which is real (cos@)

4@=pi/2+kpi= (pi+2kpi)/2= (2k+1)pi/2 where k=0,1,2,3

Agree with Tommy though, you gotta make effort yourself first, if you post up a method that you tried with your Q it shows you tried. Glad to assist though
 
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