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Completing the square!

  1. Nov 28, 2004 #1
    Hello =D I was doing an IB Project for math... and this question popped out.

    Describe a method of writing the quadratic expression x2 + bx + c in the form
    (x – h) 2 + g

    I know how to do them (complete the square) but I don't know how to describe them.

    for example, where does h and g pop out?

    If you guys could help me... it would mean so much to me =D

  2. jcsd
  3. Nov 28, 2004 #2

    Dr Transport

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    look at [tex] x^{2} + bx +(b/2)^{2} - (b/2)^{2} + c = (x+b/2)^{2} +c - (b/2)^{2} [/tex] which completes the square.....
  4. Nov 29, 2004 #3


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    You might be interested in the geometric interpretation - completing the square really IS completing the square!

    (I had to do some serious editing and compression to get it to fit - hope it works!)

    Attached Files:

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