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Thread: Geometry inequality

  1. #1
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    Geometry inequality

    Hi!Can anyone help me with this?
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  2. #2
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    Re: Geometry inequality

    WHAT is the question?
    You gave us an equation only...
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  3. #3
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    Re: Geometry inequality

    We have to proof that (4R+r)^9>=....
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  4. #4
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    Re: Geometry inequality

    Quote Originally Posted by AlexC View Post
    We have to proof that (4R+r)^9>=....
    What are we given about $\Delta ABC~?$ Is it simply any triangle?

    Some authors use $R$ for the circumradius and $r$ for the inradius. Is that the case here?
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  5. #5
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    Re: Geometry inequality

    Sorry, i found out that the problem was wrong. The correct problem is:
    In triangle Abc.
    Prove that (4R+r)^9>=19683/4*(R^2*p^6*r)
    Last edited by AlexC; Mar 10th 2018 at 02:34 PM.
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  6. #6
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    Re: Geometry inequality

    Sorry. This is the correct problem. ABC is a simply any triangle
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  7. #7
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    Re: Geometry inequality

    Quote Originally Posted by AlexC View Post
    Sorry. This is the correct problem. ABC is a simply any triangle
    That is a useless posting. Why not just post the entire question with all details?
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  8. #8
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    Re: Geometry inequality

    This is the entire question with all details. In any triangle ABC, we have to proof that (4R+r)^9>=...
    where r:inradius and R: circumradius and p- semiperimeter
    Last edited by AlexC; Mar 10th 2018 at 04:09 PM.
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