Originally Posted by

**fatman57**

thanks - could it simply be the fact that a quadratic represents a much larger number and is therfore a larger problem for a computer to solve than a linear one?

If we're talking about the "size" of a problem then my interpretation is that if you double the size of the input in a linear algorithm then the number of operations required to complete the task will also double, likewise if you triple the size of the input then 3 times as many operations will be performed. However if you double the size of the input in a quadratic algorithm then the algorithm will perform 4 times as many operations in calculating a solution. (tripling input will require 9 times as many operations) So we can see that if the algorithm is cubic then the run time will increase a lot when we start increasing the size of the problem even a little.