Finding the order of a quotient field

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Homework Statement


Find the order of ##\mathbb{Z}_3 [x] / \langle x^2 + 2x + 2 \rangle ## and ##\mathbb{Z}_3 [x] / \langle x^2 + x + 2 \rangle ##

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The Attempt at a Solution


Is there an efficient method for doing this? Is the answer 27 for both? It would seem that both of these consist of elements of the forms ##ax^2 + bx + c + \langle x^2 + 2x + 2 \rangle## or ##ax^2 + bx + c + \langle x^2 + x + 2 \rangle##, and there are three choices for the coefficients a, b, c, so ##3^3 = 27##
 
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Mr Davis 97 said:
It would seem that both of these consist of elements of the forms ##ax^2 + bx + c + \langle x^2 + 2x + 2 \rangle## or ##ax^2 + bx + c + \langle x^2 + x + 2 \rangle##
Are you sure? How did you derive this?
 
andrewkirk said:
Are you sure? How did you derive this?
Well I am not sure. But my intuition tells me that all higher order polynomials can be written as lower powers by using the ##x^2 = -2x -2## or ##x^2 = -x -2##
 
Mr Davis 97 said:
Well I am not sure. But my intuition tells me that all higher order polynomials can be written as lower powers by using the ##x^2 = -2x -2## or ##x^2 = -x -2##
What is the maximum possible order of the remainder polynomial one gets from dividing a polynomial by ##x^22+2x+2##?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...

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