posted by ash .
form a polynomial f(x) with real coefficients having the given degree and zeros
degree 4 zeros 5+3i;3 multiplicity 2
enter the polynomial
see my reply to your other question above
for a zero of 3 with multiplicity of 2
we would have (x-3)(x-3) or (x-3)^2 as part of the function.
For the complex root of 5+3i , there is of course a matching 5-3i root
once you have that , it is simple algebra