수학동아 - 폴리매스

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

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

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Function: mkdir

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 236
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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Backtrace:

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 213
Function: file_get_contents

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 236
Function: getLatexImg

File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
Line: 585
Function: parseLatexImg

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

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Line: 315
Function: require_once

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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

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Function: parseLatexImg

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함께 풀고 싶은 문제

창의력을 기를 수 있는 수학 문제 또는 퍼즐을 내는 곳입니다.

[창의 퍼즐] 명제의 증명

관종이 2020.02.06 08:23 조회 682

문제 푼 사람 1명

페이스북 트위터 카카오톡 카카오스토리 네이버블로그 네이버밴드

다음 명제들을 증명하여라.

세 개 중 두 개만 맞혀도 해결 드립니다!

1. a+b+c=3 일때, $\sqrt$ a+ $\sqrt$ b+ $\sqrt$ c가 3 이하임을 증명하여라.

2. 산술평균, 기하평균, 그리고 조화평균의 관계를 유도하여라.

3. n²이 홀수이면 n이 홀수이다.

이전글 [HME] 나무 심기

다음글 연속한 수들의 합 (난이도: 하)

이 문제 어떠셨나요?

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해결

도전

sicma Lv.11 2020.02.06 10:28 비밀댓글

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cube120 Lv.5 2020.02.07 09:12

1. 멱평균 부등식

2. 조화 <= 기하 <= 산술

3. 귀류법

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