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Mechanics question

  1. Jan 26, 2004 #1
    Suppose I am standing at the top of a cliff which is a vertical distance (d) above the ground. Now, if I jump off the slide at an angle beta upwards at an initial velocity (v), I will travel a horizontal distance of (R). I have proved the first part of the question which shows these quantities are related by the equation:

    Rsin(2beta) + d(1 + cos(2beta))=(R^2)g/v^2

    where g is 9.8 meters per second squared.

    Ok, now here is the relation which I am having problems solving:

    The condition for maximum range R is


    I have no idea how to go about showing this. Any ideas or suggestions?
  2. jcsd
  3. Jan 26, 2004 #2


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  4. Jan 26, 2004 #3

    Doc Al

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    Start by taking the derivative with respect to beta of your first relation.
    Last edited: Jan 26, 2004
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