Determine the greatest common divisor of X 4 − X 3 + 7 X 2 − 5 X + 11 {\displaystyle {}X^{4}-X^{3}+7X^{2}-5X+11} and X 3 − 6 X 2 + 4 X + 6 {\displaystyle {}X^{3}-6X^{2}+4X+6} , and a representation of it.
and 
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and a representation of it.
