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Limits and Rates of Change

  1. Sep 12, 2010 #1
    Hello there. I am kind of confused about this and have no idea where to start.
    FOr example:

    If the line given is y=x^2+4x-1 and we are to find the slope of the tangent of the perpendicular line which passes through x-coordinate -3.


    Where do I start?
     
  2. jcsd
  3. Sep 12, 2010 #2

    LCKurtz

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    Figure out what point (-3, ?) you are discussing. Then, do you know how to find the slope of a curve at a point? And do you know the relation between the slopes of two lines which are perpendicular to each other?
     
  4. Sep 12, 2010 #3
    Ohh I am sorry. Disregard the perpendicular part.
    So what I am asking is:

    How do i find the sloper of the tangent lines to the parabola y= x^2 + 4x -1 if I am only given the x-coordinate -3. That is all the information stated.

    I need help from step one. I have no idea how to even approach this.
     
  5. Sep 12, 2010 #4

    LCKurtz

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    Well, surely you can figure out the y value for x = -3.

    Are you taking a calculus course? Do you know about derivatives and their relation to slope?
     
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