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Homework Help: Finding a,b from roots of equition

  1. Mar 11, 2010 #1
    1. The problem statement, all variables and given/known data

    If x = -1; 1 are the two roots of the equation x^2 +ax+b = 0; then find the values of a and b.



    3. The attempt at a solution

    x^2+ax+b=0

    (x-1) (x+1)= 0 ,,,,,, by expanding

    x^2-1=0 ,,,,, so a=0 , b=-1

    is it right or the question is asking for something eles,,,, ?
     
  2. jcsd
  3. Mar 11, 2010 #2
    look slike you got it.
     
  4. Mar 11, 2010 #3
    yay ,,,

    look like am getting better everyday ^^

    thx to this forums
     
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