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Homework Help: Polar coordinates, maximum distance.

  1. Aug 15, 2011 #1
    1. The problem statement, all variables and given/known data
    The diagram (omitted) shows the curve C with polar equation r=e^(\theta), where 0\le\theta\le(pi/2). Find the maximum distance of a point of C from the line \theta=(pi/2), giving the answer in exact form.

    3. The attempt at a solution

    I'm not really sure how to attack this; it says in the examiners report that one needs to write x as e^(theta).cos(theta), but I can't see why this is...
     
  2. jcsd
  3. Aug 15, 2011 #2

    HallsofIvy

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    The line [itex]\theta= \pi/2[/itex] is just the vertical line x= 0, the y-axis and the distance from any point (x, y) to that line is just x. And, of course, [itex]x= r cos(\theta)[/itex]. That is what you want to maximize.
     
  4. Aug 15, 2011 #3
    OMG I THOUGHT THE LINE WAS theta=pi/4 ... sigh...
     
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