Square-free factorization : sqrfree

### 2.24.14 Square-free factorization : `sqrfree`

`sqrfree` takes as argument a polynomial.
`sqrfree` factorizes this polynomial as a product of powers of coprime factors, where each factor has roots of multiplicity 1 (in other words, a factor and it’s derivative are coprime).
Input :

`sqrfree((x```^```2-1)*(x-1)*(x+2))`

Output :

`(x```^```2+3*x+2)*(x-1)```^```2`

Input :

`sqrfree((x```^```2-1)```^```2*(x-1)*(x+2)```^```2)`

Output :

`(x```^```2+3*x+2)*(x-1)```^```3`