Let f(x) = x3 - 6x2 + 11x - 6.
Then, which one of the folllowing is not a factor of f(x) ? 

C. X + 3

The Polynomial (x4 - 5x+ 5x2 - 10x + 24) has a factor as :

B. X - 2

If (x + 1/x) = 2, then (x31/x3) is equal to :

D. 2

If (x + 1/x) = 3, then (x21/x2) is equal to :

C. 7

If x + y = 7 and xy = 6,
the value of (x3 + y3) is : 

C. 217