Find all roots of a high-order equation

The math behide this solution is quite simple:
if a polynomial equation f(x)=0 has roots, let's say x1,x2,……xn,then f(x) can be converted to another format as (x-x1)*(x-x2)*(x-x3)*…...*(x-xn) = 0
So what we do here is use goal-seek to find it's first root(x1)
then use f(x) / (x-x1) as a new equation, easy to say the new one is (x-x2)*(x-x3)*…...*(x-xn) = 0
repeat the procedure above,we can get all the roots one by one.