SOLUTION: This is related to quadratic equations and complex numbers. The equation is x^2+mx+n=0 One of the roots/solutions is 3+2i. What is the value of m?

Question 176455: This is related to quadratic equations and complex numbers. The equation is x^2+mx+n=0 One of the roots/solutions is 3+2i. What is the value of m?
Found 2 solutions by EMStelley, Mathtut:
Answer by EMStelley(208) (Show Source): You can put this solution on YOUR website!
To solve this problem you need to know a property of quadratic equations with complex roots. If a+bi is a solution of a quadratic equation, so is a-bi. So since 3+2i is a solution, 3-2i is also. Now, since 3+2i is a solution, that means that (x-(3+2i)) is a factor. Thus (x-(3-2i)) is a factor also. So if we multiply the two together, we should get our equation.

Thus, m=-6.
Answer by Mathtut(3670) (Show Source): You can put this solution on YOUR website!
if one solution is 3+2i then the other is 3-2i
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value of m=-6
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