Find a polynomial equation with real coefficients that has the given roots 8i and the square root of 7.

Answer 1

(x-8i)(x+8i) (x - rad7)

You said REAL coefficients not RATIONAL coefficients...

(x^2+64)(x - rad7) =

x^3 - rad7 * x^2 + 64x - 64*rad7

IF you want RATIONAL coefficients then (x+ rad7) is also a factor, which forces

x = -rad7 to be the 4th solution