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Homework Help: Equation of secant line

  1. Jan 28, 2008 #1
    Wow, someone asked me this question and I'm stumped.

    Find the equation of the secant line that contain [tex]P[0,f(0)][/tex] and [tex]Q[3,f(3)][/tex]

    Am I given enough information to solve this?

    [tex]m=\frac{f(x+h)-f(x)}{h}[/tex]

    ...

    [tex]m_1=\frac{f(h)-f(0)}{h}[/tex]

    [tex]m_2=\frac{f(3+h)-f(3)}{h}[/tex]

    That doesn't really help me though, unless I'm not thinking hard enough!
     
    Last edited: Jan 28, 2008
  2. jcsd
  3. Jan 28, 2008 #2

    rock.freak667

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    Isn't a secant line just a straight line with those two points?

    uhm....

    [tex]m=\frac{f(3)-f(0)}{3-0}[/tex]


    but the answer would be in terms of f(3) and f(0)
     
    Last edited: Jan 28, 2008
  4. Jan 28, 2008 #3
    Yeah and I'm given 2 points and I need to find an equation that contains both. Hmm.
     
  5. Jan 28, 2008 #4
    Oh I think I got it now, haha. My brain finally kicked in.
     
  6. Jan 28, 2008 #5

    rock.freak667

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    What was it? Finding the equation of a line given two points? Or was my brain malfunctioning as well?
     
  7. Jan 28, 2008 #6
    Yeah, seems like the only thing to do.

    [tex]m=\frac{f(3)-f(0)}{3}[/tex]

    [tex]y-f(0)=\frac{f(3)-f(0)}{3}(x-0)[/tex]

    Not sure what else to think of.
     
  8. Jan 28, 2008 #7

    rock.freak667

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    I would hope that is all there is to it.
     
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