Question

If x = i Root of 6 is one zero of the function: y = x3 + 3x2 + 6x + 18, find the other zeros.?

Answer 1

please help!

Answer 2

if \[i\sqrt{6}\] is a root then so is

\[-i\sqrt{6}\]

and your polynomial has the two factors \[(x-i\sqrt{6})(x+i\sqrt{6})\]

Answer 3

\[(x-i\sqrt{6})(x+i\sqrt{6})=x^2+6\]

so \[x^3 + 3x^2 + 6x + 18=(x-a)(x^2+6)\]

thus a=-3 ( we need -a*6=18)


so the roots are \[-3,i\sqrt{6},-i\sqrt{6}\]

Answer 4

THANK UUUUU!!! ZARKON!!