Remember
that if is a zero, then it’s complex conjugate, i.e. is also a zero. So, to find the other zero, you need to swap the sign in front of the
imaginary term.
1 : If the complex number is a zero of the polynomial , what other number do you know must be a zero of ?
2 : If the complex number is a zero of the polynomial , what other number do you know must be a zero of ?
Remember
that if is a zero, then it’s complex conjugate, i.e. is also a zero. So, to find the other zero, you need to swap the sign in front of the
imaginary term.