Question 1120156
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a)  x^10-x^8-2x^4-1 = x^10 - (x^8 +2x^4 + 1) = x^10 - (x^4+1)^2 = 


    = (x^5 - (x^4+1))*(x^5 + (x^4+1)) = (x^5 - x^4 - 1)*(x^5 + x^4 + 1).
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