I remember dis, yey
so if a polynomial has roots
, 
, 
, it can be factored into
where a,b,c,d are constants
also, if a polynomial has rational coefients and a+bi is a root, then a-bi must also be a root
so our roots we need are
4,16, 1+9i and 1-9i
so assuming multiplity 1 (that means we have something like [/tex]f(x)=a(x-r_1)^1(x-r_2)^1(x-r_3)^1[/tex])
we get that your function is
which simplifies to
which expands to
so if a polynomial has roots
also, if a polynomial has rational coefients and a+bi is a root, then a-bi must also be a root
so our roots we need are
4,16, 1+9i and 1-9i
so assuming multiplity 1 (that means we have something like [/tex]f(x)=a(x-r_1)^1(x-r_2)^1(x-r_3)^1[/tex])
we get that your function is