sympy/sympy — pull request #824 by smichr (2011-12-06 12:16:10+00:00)
Title: Radical content removal

radicals with Integer bases can now be factored out of the primitive portion of an expression:

```python
>>> (root(3,3)*root(27*2,3)**2+root(6,3)).as_content_primitive()
(1, 6**(1/3)*(1 + 9*2**(1/3)))
```

Since factor_terms relies on as_content_primitive, this means that factor_terms will also be able to factor out such terms

```python
>>> factor_terms(sqrt(2+2*x)+sqrt(10+10*x))
sqrt(2)*(1 + sqrt(5))*sqrt(x + 1)
```