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Math Help - help in Integral Maximization

  1. #16
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    And this shape isn't any of those. Take a look here and see if any of those shapes match what you have.
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  2. #17
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    Quote Originally Posted by Ackbeet View Post
    And this shape isn't any of those. Take a look here and see if any of those shapes match what you have.
    trapezium
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  3. #18
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    Close, but I think you know even more than that. Remember that two sides of this thing are vertical. What does that tell you?
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  4. #19
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    Quote Originally Posted by Ackbeet View Post
    Close, but I think you know even more than that. Remember that two sides of this thing are vertical. What does that tell you?
    right angled trapezium
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  5. #20
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    Don't get discouraged! You're making great progress.

    Here in America, we call that a trapezoid. I see that the Brits call it what you called it. That's fine. What is the area of a trapezoid?
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  6. #21
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    Quote Originally Posted by Ackbeet View Post
    Don't get discouraged! You're making great progress.

    Here in America, we call that a trapezoid. I see that the Brits call it what you called it. That's fine. What is the area of a trapezoid?
    area = 0.5*h* (s1+s2)
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  7. #22
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    but i want to know should i check each value from x with each value with y
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  8. #23
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    Correct area calculation. I would now employ the trapezoidal rule to formulate the (exact) area under a sequence of joined piecewise linear segments. Question: are the x-coordinates evenly spaced? If so, you can use the usual composite trapezoidal rule. If not, you have to use the formula for non-uniform intervals, as also provided in the link.

    In answer to your Post # 22, I would say yes: you must check every permutation, essentially. There might be a way to short-cut this, if you can see some theorem or other that you can prove. For example: take a close look at the formula for uniform intervals. Do you notice anything about it?
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  9. #24
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    Quote Originally Posted by Ackbeet View Post
    Correct area calculation. I would now employ the trapezoidal rule to formulate the (exact) area under a sequence of joined piecewise linear segments. Question: are the x-coordinates evenly spaced? If so, you can use the usual composite trapezoidal rule. If not, you have to use the formula for non-uniform intervals, as also provided in the link.

    In answer to your Post # 22, I would say yes: you must check every permutation, essentially. There might be a way to short-cut this, if you can see some theorem or other that you can prove. For example: take a close look at the formula for uniform intervals. Do you notice anything about it?
    i think there is something better
    h= each(x2-x1)
    and i must sort the y values and sort the height values
    then take smallest highet with smallest y1-y2 after sorting and son on ... what is your opinion
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  10. #25
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    So, are the x-intervals uniform, then?
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  11. #26
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    Quote Originally Posted by Ackbeet View Post
    So, are the x-intervals uniform, then?
    i will check my answer if it is accepted i will tell u if not i will tell u so
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  12. #27
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    What do you mean, "accepted"?
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  13. #28
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    Quote Originally Posted by Ackbeet View Post
    What do you mean, "accepted"?
    that my solution is right and all test cases on it will be right
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  14. #29
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    Oh, ok.

    I have my theory, finally. I haven't proved it yet, but I'm fairly sure it's correct.
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  15. #30
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    Quote Originally Posted by Ackbeet View Post
    Oh, ok.

    I have my theory, finally. I haven't proved it yet, but I'm fairly sure it's correct.
    ok tell me
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