Question 1135463
multiplicity 2 means squared and zero of 1 means factor x-1
(x-1)^2 is part of this
4i is a root, so -4i is one
factors are (x-4i) and (x+4i)
they multiply to x^2+16
the other multiplies to (x^2-2x+1)
the polynomial is x^4-2x^3+x^2+16x^2-32x+16
or x^4-2x^3+17x^2-32x+16
{{{graph(300,300,-10,10,-10,10,x^4-2x^3+17x^2-32x+16)}}}