6. Find the polynomial function with roots 11 and 2i
one more root exists which is the conjugate of 2i. what is the conjugate of 2i?
Well 2i would have 2 pairs because it is imaginary. And we know one of the binomials will be (x-11)
So basically (x-11)(x-2i)(x+2i) And what you need to know to solve this is that i^2=-1.
So first FOIL (x-2i)(x+2i) and then when you get that distribute (x-11) to that. And remember i^2=-1. Does that make sense @Smartzman?
yes thank you very much :)
I have the answer I can check yours when you get it!
ok one moment
x^3-11x^2+4x-44
is what I got
:) or : (
:-) Now, I feel obligated to point out that there is not just one polynomial with those roots. There's an infinite variety of them, obtained by putting a constant multiplier in the mix with your (x-root) factors. So, either you should multiply by that constant, or harass the teacher about sloppy question-writing :-)
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