# `roots` doesn't find all roots of a polynomial

Let's consider the following example:

```
w = x^4 - (1+3*i)*x^3 - (2-4*i)*x^2 + (6-2*i)*x - 4 - 4*i
p = x^4 + (1-3*i)*x^3 - (4-3*i)*x^2 - (4-2*i)*x + 2*i
solve(w, x)
w.roots()
```

When using `solve`

, all complex roots are found. When using `roots`

, only two of them. Why?