# common factor in symbolic expressions

Is there any way of extracting a common factor of all terms in a list of symbolic expressions?

For example, in the following list

```
[x^4*cos(x), x^3*cos(x), x^2*cos(x)*sin(x)]
```

such function should return `x^2*cos(x)`

. And for

```
[1/x^4*cos(x), 1/x^3*cos(x), 1/x^2*cos(x)*sin(x)]
```

it should return `1/x^2*cos(x)`

.