This function computes the square-free part of the polynomial f. That is, it computes g so that $\gcd \left(g\,f\right)=g$ and $g$ has no repeated factors.

$\mathrm{with}\left(\mathrm{PolynomialTools}\right)\:$

$\mathrm{SquareFreePart}\left(\left(x+y+1\right)\mathrm{expand}\left({\left(x+y+1\right)}^2\right){\left(x-y-3\right)}^3\left(3x+6y-21\right)\,\left\{x\,y\right\}\right)$

$\left(x+y+1\right)\left(x-y-3\right)\left(x+2y-7\right)$

$\mathrm{SquareFreePart}\left(A-\exp \left(x\right)\right)$

$A-{\ⅇ}^x$

The PolynomialTools[SquareFreePart] command was updated in Maple 2017.