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Homework Help: Tangent lines

  1. May 9, 2007 #1
    1. The problem statement, all variables and given/known data
    Given: [tex]f(x)=x^2-4x+5[/tex] find equation for two lines that are tangent to the graph and pass through the point P(0,1)

    2. Relevant equations
    Equation of the tangent line/s
    [tex] f(x)=f'(a)(x-a)+f(a)[/tex]

    3. The attempt at a solution
    Just need to get started
  2. jcsd
  3. May 9, 2007 #2


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    Staff Emeritus
    Science Advisor
    Gold Member

    You seem to have everything you need. You have the derivative, which gives you the slope of the tangent line at any point you plug in. You're supposed to find the tangent line at the point (0, 1), which means you need the slope at x=0. You can use point-slope form to find the line equation if you want, or you can literally just plug the numbers into the general line equation you were given.

    - Warren
  4. May 9, 2007 #3
    lol... revelation I got it.
    Don't you love it when you make things more complicated then they need to be?:rofl:
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