Let f(x)=x3-6x2+11x-6.
Look for rational zeroes, so break 6 down into factors: 1, 2, 3, 6.
Set x to each of these (positive and negative) and test for zero until a zero is found (if any):
f(1)=1-6+11-6=0, so x=1 is a zero and x-1 is a factor. Use synthetic division to reduce to a quadratic:
1 | 1 -6 11 -6
1 1 -5 | 6
1 -5 6 | 0 = x2-5x+6=(x-2)(x-3).
So x3-6x2+11x-6=(x-1)(x-2)(x-3).