수학동아 - 폴리매스

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

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

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Function: require_once

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Line: 315
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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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

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Function: getFloatingMyInfo

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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] [조합]선들 사이의 교점

△π 2020.06.06 22:15 조회 739

문제 푼 사람 0명

페이스북 트위터 카카오톡 카카오스토리 네이버블로그 네이버밴드

(로고는 지나가던 사람님께서 만들어 주셨습니다!)

(1)평면 위에 다섯 개의 점이 놓여 있는데, 이 점들을 잇는 어떤 두 직선도 서로 평행하거나, 수직하거나, 또는 일치하지 않는다고 하자. 각각의 점에서 그 점을 지나고, 나머지 네 점으로 이루어진 6개의 변과 수직인 직선을 그린다. 이러한 직선들이 만나는 교점의 최대 개수를 구하여라.

(2)평면 위에 n개의 점이 놓여 있는데, 이 점들을 잇는 어떤 두 직선도 서로 평행하거나, 수직하거나, 또는 일치하지 않는다고 하자. 각각의 점에서 그 점을 지나고, 나머지 n-1개의 점으로 이루어진 $\binom{n-1}{2}$ 개의 변과 수직인 직선을 그린다. 이러한 직선들이 만나는 교점의 최대 개수를 구하여라.

이전글 [무한]도배신의 무한한 도배

다음글 [피타] 빗변의 길이가 1인 직각삼각형(1)

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