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함께 풀고 싶은 문제

창의력을 기를 수 있는 수학 문제 또는 퍼즐을 내는 곳입니다.

[창의 퍼즐] 쉬워 보이지만 어려운 문제

sincostan 2019.02.20 07:11 조회 1536

문제 푼 사람 0명

페이스북 트위터 카카오톡 카카오스토리 네이버블로그 네이버밴드

(1)x+2=2x를 만족하는 x를 2개이상 찾아라.

(2)x=y에서 x,y가 독립변수일때

이런 x,y순서쌍을 찾아라.

이전글 왕관을 얻는 방법

다음글 새로 만든 하노이탑 가능할까?

이 문제 어떠셨나요?

글쎄요

어려워요

문제 찜하기 목록보기

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아인수타인 Lv.12 2019.02.20 10:41

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2개요...? $x=2$ 인 거 하나밖에 안 나오는데... 그리고, 2번은 저걸 만족하는 거 자체가 무한한데요...?

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- 21세기오일러 Lv.11 2019.02.20 19:04
  
  그러게요 . 1번은 양변에 x를 빼면 x=2로 나오고 2번도 답이 무한한데
  
  좋아요0
- K-RIEMANN Lv.10 2019.03.18 00:22
  
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  File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
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  Filename: 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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  File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
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  Filename: libraries/Common.php
  
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  File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
  Line: 202
  Function: mkdir
  
  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/views/ver3/inc/view_comment_list.php
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  Function: parseLatexImg
  
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  Function: view
  
  File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
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  Function: require_once
  
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  Filename: libraries/Common.php
  
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  File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/libraries/Common.php
  Line: 213
  Function: file_put_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/views/ver3/inc/view_comment_list.php
  Line: 200
  Function: parseLatexImg
  
  File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/views/ver3/inc/view.php
  Line: 343
  Function: view
  
  File: /volume1/web/PhpstormProjects/www_polymath_co_kr/application/controllers/ver3/Contents.php
  Line: 558
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  Function: require_once
  
  $x$ 가 자연수맞죠?
  
  $\sqrt{4}$ 같은건 아니죠?
  
  좋아요0
- sincostan Lv.7 2019.03.18 09:05
  
  딱히 자연수라는 조건은 없습니다.
  
  좋아요0
초코Pi Lv.1 2019.02.21 02:57

1번 답이 혹시 2, 루트 4 이런거 아닐까요?

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sincostan Lv.7 2019.02.21 09:27

아닙니다.제가 문제를 잘못낸 것은 절대아니고 2번은 x와y가 서로 다릅니다.

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- 아인수타인 Lv.12 2019.03.11 05:42 비밀댓글
  
  비밀 댓글이 등록 되었습니다!
- sincostan Lv.7 2019.03.11 05:43
  
  정답입니다.
  
  좋아요1
초등의꿈 Lv.1 2019.03.02 08:21

x+2=2x (mod 2) 는

x=0(작대기 3개 가 안되서 그냥 두개로 합니다

and

x=2

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- sincostan Lv.7 2019.03.03 01:12
  
  아닙니다.
  
  좋아요0
K-RIEMANN Lv.10 2019.04.10 03:00

잘하면 2와 2.0일수도 있을 것 같은데요??

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