Form a polynomial​ f(x) with real coefficients having the given degree and zeros.

Degree​ 4; ​ zeros: 2​, multiplicity​ 2; 3i

1 answer

if r is a root (zero) , then x-r is a factor

factors ... (x - 2) (x - 2) (x + 3i) (x - 3i)

multiply the factors to form the polynomial

complex roots (with i in them) occur in conjugate pairs ... (x + i) & (x - i)