### 2.24.15 List of factors : `factors`

`factors` has either a polynomial or a list of polynomials as argument.
`factors` returns a list containing the factors of the polynomial and their exponents.
Input :

`factors(x```^```2+2*x+1)`

Output :

`[x+1,2]`

Input :

`factors(x```^```4-2*x```^```2+1)`

Output :

`[x+1,2,x-1,2]`

Input :

`factors([x```^```3-2*x```^```2+1,x```^```2-x])`

Output :

`[[x-1,1,x```^```2-x-1,1],[x,1,x-1,1]]`

Input :

`factors([x```^```2,x```^```2-1])`

Output :

`[[x,2],[x+1,1,x-1,1]]`