I’ve been trying to figure out how to factor cubic equations by studying a few worksheets online such as the one [here](http://salinesports.org/mr_frederick/Algebra%202A/Unit%206/Notes_0605.pdf) and was wondering is there any generalized way of factoring these types of equations or do we just need to remember a bunch of different cases. 

For example, how would you factor the following: 

> 
> $x^3 – 7x^2 +7x + 15$
> 
> 
> 

I'm have trouble factoring equations such as these without obvious factors.