How to find the gcd of f(x)=x^{2}- x-2 and g(x)= x^{3}-7x+6 in F_{3}[x]. Expressed as a linear combination of f,g.

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- May 4th 2013, 08:34 PMkayabi5Find gcd
How to find the gcd of f(x)=x

^{2}- x-2 and g(x)= x^{3}-7x+6 in F_{3}[x]. Expressed as a linear combination of f,g. - May 4th 2013, 09:22 PMibduttRe: Find gcd
factorize f(x) and g(x) .

the product of common factors will be the gcd. - May 5th 2013, 03:13 AMabualabedRe: Find gcdhello every one
- May 5th 2013, 06:18 PMkayabi5Re: Find gcd
Ok, but what throws me off is the F3[x]. I know its (0,1,2), but how to you apply it?

- May 6th 2013, 06:20 AMHallsofIvyRe: Find gcd
So we are dealing in modulo 3. The first thing I would do is simplify : 7= 1 (mod 3) and 6= 0 (mod 3). So which we could also write as x(x+2)(x+1). To factor , look at the general . We need to find a and b such that a+ b= 2 (mod 3) and ab= 1 (mod 3). a= b= 1 should be obvious.