I would like some help with this.
The equation is given.
Show that one of the roots are i.
So i verified that i is indeed a root. And since complex roots are "mirrored", another root must be -i.
The factor theorem.
Then i factored the equation using polynomial division and the result is
the second bracket is a simple quadratic.
This is where i get it wrong, isn't the square root expression supposed to evaluate to 2i ?
The correct answer is however, the result im getting is