SOLUTION: According to the conjugate root theorem, if a polynomial with rational coefficients has -1+√6; -2√2; -3-i as roots, what are the other roots?

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Question 1128236: According to the conjugate root theorem, if a polynomial with rational coefficients has -1+√6; -2√2; -3-i as roots, what are the other roots?
Found 2 solutions by MathLover1, ikleyn:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
if a polynomial with rational coefficients has
-1%2Bsqrt%286%29
+-2sqrt%282%29
+-3-i as roots,
according to the conjugate root theorem, the other roots are: +-3%2Bi

Answer by ikleyn(52864) About Me  (Show Source):
You can put this solution on YOUR website!
.
There are TWO conjugate root theorems:


    One (the most widely known) conjugate root theorems says:


        If a polynomial with real coefficients has a root a+bi with real "a" and "b",  and  i = sqrt%28-1%29, 
        then it has the root  a-bi,  too.



    The other conjugate root theorem says:


        If a polynomial with rational coefficients has a root a%2Bb%2Asqrt%28c%29 with rational "a" and "b", 
        then it has the root a-b%2Asqrt%28c%29, too.



By applying one and another conjugate root theorem to the given problem, we obtain that

    the root -1%2Bsqrt%286%29 goes in pair with the root  -1-sqrt%286%29;

    the root -2%2Asqrt%282%29 goes in pair with the root  2%2Asqrt%282%29;

    the root -3-i goes in pair with the root  -3%2Bi.


So, the polynomial has, in total, 6 (six; SIX) listed roots.

Solved, answered and completed.