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| Question 1068321:  Find a polynomial f (x) of degree 3 with real coefficients and the following zeros.  4, 3+i
 f (x) = _____
 Appreciate help on this question. I believe it is asking for zeros, only two zeros given, need to find the third zero. ( think that is what this question is asking). Need step-by-step solution.
 Answer by ankor@dixie-net.com(22740)
      (Show Source): 
You can put this solution on YOUR website!  Find a polynomial f (x) of degree 3 with real coefficients and the following zeros. 4, 3+i :
 from the zeros given we can make two factors
 x = 4
 (x-4) = 0
 and
 x = 3 + i
 x - 3 = i
 Square both sides
 (x-3)^2 = i^2
 FOIL (x-3()x-3), i^2 is -1
 x^2 - 6x + 9 = -1
 x^2 - 6x + 9 + 1 = 0
 x^2 - 6x + 10 = 0
 Make an equation using these two factors
 f(x) = (x-4)*(x^2-6x+10)
 multiply these two factors, results:
 f(x) = x^3 - 10x^2 + 34x - 40
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