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Homework Help: Additional maths help please

  1. Sep 30, 2008 #1
    additional maths help please!!

    My minds gone blank. How do I solve this
    Find the equations of the tangents to the curve y=(2x-1)(x+1) at the points where the curve cuts the x axis. Find the point of intersection of these tangents.
    Thanks
    Emmab
     
  2. jcsd
  3. Sep 30, 2008 #2
    Re: additional maths help please!!

    First find the tangent equation using differentiation, then find the points where the curve cuts the x-axis and plug in.
     
  4. Sep 30, 2008 #3

    HallsofIvy

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    Science Advisor

    Re: additional maths help please!!

    I would be inclined to do it the other way around! First find the x-values where the curve crosses the x-axis (y= 0 there), then find the derivative at those values of x. No real difference, of course.
     
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