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Problem on test today

  1. Dec 10, 2004 #1
    There was a question on my math test today and i didnt even understand the problem. I want to see if anyone else knows how to do it. So here it goes:
    "Use Calculus to prove which vertex angle an isoseles triange the greatest area"

    I think your supposed to find a equation for Area and Perimeter. Then take one of the equations and solve for a variable. Plug it into the next equation and then differentiate, like i would do on optimization problems, but i didnt know how to do it with this problem. Below is the figure given.

    Attached Files:

  2. jcsd
  3. Dec 10, 2004 #2


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    I'm not sure,there might be more to your problem than what i understood:
    [tex] S_{triangle} =\frac{k^{2}\sin\theta}{2} [/tex],where k and k are the 2 sides of the isosceles triangle assuled constant and the angle [itex] \theta [/itex] is the angle between the 2 congruent segments.
    This of S as a function of only one variable,the angle [itex] \theta [/itex] and use the principle of extremum to find the angle for which the area is maximum.Then find that maximum inserting the value for maxmum in the initial function.

    As i said,maybe the problem is more complicated,but for now,try to solve it this way.

  4. Dec 10, 2004 #3
    k thankssss :smile:
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