Answer:
p(x) = x^2 - 8x + 41
Step-by-step explanation:
If a polynomial with rational coefficients has a complex root, then the roots come in complex conjugate pairs. If the polynomial we need to find has the root 4 - 5i, then it must also have its complex conjugate 4 + 5i as a root.
p(x) = [x - (4 - 5i)][x - (4 + 5i)]
p(x) = [(x - 4) + 5i][(x - 4) - 5i]
Now it's a difference of two squares.
p(x) = (x - 4)^2 - (5i)^2
p(x) = x^2 - 8x + 16 + 25
p(x) = x^2 - 8x + 41
