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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Cacher.php
Line: 22
Function: driver
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Cacher.php
Line: 17
Function: initiateCache
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/index.php
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Backtrace:
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Cacher.php
Line: 22
Function: driver
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Cacher.php
Line: 17
Function: initiateCache
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
Line: 14
Function: __construct
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/index.php
Line: 315
Function: require_once
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/models/ver3/Contents_model.php
Line: 17
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: initMenu
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
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Function: __construct
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/index.php
Line: 315
Function: require_once
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/models/ver3/Contents_model.php
Line: 18
Function: _error_handler
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 440
Function: model
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 29
Function: initMenu
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
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Function: __construct
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/index.php
Line: 315
Function: require_once
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Filename: libraries/Driver.php
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Backtrace:
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/models/ver3/Contents_model.php
Line: 799
Function: get
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
Line: 605
Function: getComment
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
Line: 315
Function: require_once
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/models/ver3/Article_model.php
Line: 18
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
Line: 559
Function: get_footer
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/index.php
Line: 315
Function: require_once
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Filename: ver3/Article_model.php
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File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/models/ver3/Article_model.php
Line: 19
Function: _error_handler
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 322
Function: model
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
Line: 392
Function: getFloatingMyInfo
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
Line: 559
Function: get_footer
File: /volume1/web/PhpstormProjects/www_polymath_co_kr/index.php
Line: 315
Function: require_once
수학동아 - 폴리매스
함께 풀고 싶은 문제
창의력을 기를 수 있는 수학 문제 또는 퍼즐을 내는 곳입니다.
조곰팅
2019.11.24 19:34
조회 527
이항연산 @가 정의된 집합 G에서 G와 @가 다음 조건을 만족할때 (G, @)를 군이라 한다
1) G의 임의의 세 원소 a,b,c 에 대해 (a@b)@c=a@(b@c) 가 성립한다
2) G에 속하는 특정 원소 e가 존재하여 G의 임의의 원소 a에 대해
a@e=e@a=a 가 성립한다 (이때 e를 항등원이라 한다)
3)각각의 G의 원소 a에 대해 a@b=b@a=e 를 만족하는 G의 원소 b가 존재한다 (이를 a에 대한 역원이라 한다)
문제: 군에서 항등원과 한 원소에 대한 역원은 유일함을 증명하여라
시리즈로 여러문제 낼 예정
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조곰팅
Lv.5
2019.11.24 19:35
이 문제 푼 분이 생기면 다음문제 올리겠습니다
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조곰팅
Lv.5
2019.11.24 20:20
좋아요1
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delta
Lv.7
2019.11.24 23:03
저거 3번 조건은 아벨 군이 되는 조건인데...
역원은 (a@b)@c = a 인 c의 존재입니다.
이때 c는 b에 대한 역원
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조곰팅
Lv.5
2019.11.25 00:13
?
아벨군 조건은 교환법칙이고요
저기서 E가 항등원입니다
좋아요1
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디듀우
Lv.7
2019.11.25 01:20
그러면 아벨 군이 군보다 큰 게 되나요? 교환법칙이 성립해야 항등원, 역원도 생길텐데... 뭔가 이름은 특수한 군 같이 지어 놓아서 헷갈리네요.
좋아요0
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