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ehrenfest
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[SOLVED] group theory problem
Find all solutions of the equation x^3-2x^2-3x=0 in Z_12.
We first factor the polynomial into x(x-3)(x+1)=0. Recall that Z_12 is not an integral domain since 12 is not prime (e.g. 3*4=0). Therefore setting each factor equal to 0 WILL NOT GIVE ALL OF THE SOLUTIONS.
Obviously, the solutions to x=0, (x-3)=0, (x+1)=0, x(x-3)=0, x(x+1) = 0, (x-3)(x+1)=0 will also be solutions to our equation. I can find all of those. The problem is that I do not know how to find the remaining ones.
Homework Statement
Find all solutions of the equation x^3-2x^2-3x=0 in Z_12.
Homework Equations
The Attempt at a Solution
We first factor the polynomial into x(x-3)(x+1)=0. Recall that Z_12 is not an integral domain since 12 is not prime (e.g. 3*4=0). Therefore setting each factor equal to 0 WILL NOT GIVE ALL OF THE SOLUTIONS.
Obviously, the solutions to x=0, (x-3)=0, (x+1)=0, x(x-3)=0, x(x+1) = 0, (x-3)(x+1)=0 will also be solutions to our equation. I can find all of those. The problem is that I do not know how to find the remaining ones.