factoriser f(x)=(x*x*x)-11x+14

f(2) = 8-22+14 = 0 donc f(x) est divisible par x-2. appliquons Hörner

            1         0         -11        14

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2                     2            4        -14

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            1         2            -7         0

x³ -11x +14 = (x-2)(x² +2x -7) = (x-2)(x + 1 + 2rac(2))(x+1-2rac(2))