수학동아 - 폴리매스

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Function: driver

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Function: model

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
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Function: initBoardView

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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Function: file_put_contents

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
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Function: parseLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
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Function: initBoardView

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/index.php
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Function: require_once

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Function: require_once

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Function: _error_handler

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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Function: model

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
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Function: get_footer

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/index.php
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Function: require_once

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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/models/ver3/Article_model.php
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Function: _error_handler

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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Function: model

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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Function: getFloatingMyInfo

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
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Function: get_footer

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/index.php
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Function: require_once

함께 풀고 싶은 문제

창의력을 기를 수 있는 수학 문제 또는 퍼즐을 내는 곳입니다.

[창의 퍼즐] [기하] 무게중심이 내접원 위에

△π 2020.10.25 14:10 조회 444

문제 푼 사람 0명

페이스북 트위터 카카오톡 카카오스토리 네이버블로그 네이버밴드

삼각형 ABC의 무게중심 G가 내접원 위에 있다. 이 때, 삼각형 ABC의 외접원의 반지름의 길이를 R, 내접원의 반지름의 길이를 r이라 할 때,

$R\geq nr$ 이 성립한다.

(1)n의 최댓값을 구하여라.

(2)등호성립 조건을 구하여라.

(3)n에 최댓값을 대입한 부등식을 증명하여라(1번에서 이미 했으면 패스)

이전글 [대수] 제곱이 여러개

다음글 [기하?조합?] 격자점을 지나는 다섯개의 원

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