Question 144119
6x^2 - 28x + 16 
= 2(3x^2 - 14x + 8)
= 2(3x^2-12x-2x+8)
= 2(3x(x-4)-2(x-4))
= 2(x-4)(3x-2)
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x^4 + 2x^3 - 3x - 6 
= x^3(x+2) -3(x+2)
= (x+2)(x^3-3)
= [(x+2)][(x-3^(1/3))][x^2-3(x^(1/3))+3^(2/3)]
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x^8 - 1 (x^4+1)(x^4+1)
= (x^4+1)(x^2+1)(x+1)(x-1)
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Cheers,
Stan H.