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1) ÇÔ¸ÕᨡᨧÊÁÒªÔ¡ (Tubular form) ÁÕËÅÑ¡¡ÒÃà¢Õ¹ ´Ñ§¹Õé
  1. à¢Õ¹ÊÁÒªÔ¡·Ñé§ËÁ´ã¹Ç§àÅ纻ա¡Ò
  2. ÊÁÒªÔ¡áµèÅеÑǤÑè¹´éÇÂà¤Ã×èͧËÁÒ¨ØÅÀÒ¤ (,)
  3. ÊÁÒªÔ¡·Õè«éӡѹãËéà¢Õ¹à¾Õ§µÑÇà´ÕÂÇ
  4. 㹡óշÕè¨Ó¹Ç¹ÊÁÒªÔ¡ÁÒ¡ æ ãËéà¢Õ¹ÊÁÒªÔ¡ÍÂèÒ§¹éÍ 3 µÑÇáá áÅéÇãªé¨Ø´ 3 ¨Ø´ (Tripple dot) áÅéǨ֧à¢Õ¹ÊÁÒªÔ¡µÑÇÊØ´·éÒÂ

2) ÇԸպ͡à§×è͹䢢ͧÊÁÒªÔ¡ (Set builder form) ËÅÑ¡¡ÒÃà¢Õ¹Áմѧ¹Õé
  1. à¢Õ¹૵´éÇÂǧàÅ纻ա¡Ò
  2. ¡Ó˹´µÑÇá»Ãá·¹ÊÁÒªÔ¡·Ñé§ËÁ´µÒÁ´éÇÂà¤Ã×èͧËÁÒ | (| ÍèÒ¹ÇèÒ "â´Â·Õ")è áÅéǵÒÁ´éÇÂà§×è͹䢢ͧµÑÇá»Ã¹Ñé¹ ´Ñ§ÃٻẺ {x | à§×è͹䢢ͧ x}/LI>

  à«µÇèÒ§ (Empty Set)  ¤×Í à«µ·ÕèäÁèÁÕÊÁÒªÔ¡àÅ à¢Õ¹᷹´éÇ { } ËÃ×Í (phi) àªè¹
  • ૵¢Í§¨Ó¹Ç¹àµçÁ·ÕèÍÂÙèÃÐËÇèÒ§ 1 ¡Ñ¹ 2
  • ૵¢Í§ÊÃÐ㹤ÓÇèÒ "ÍÃÇÃó"

  à«µ¨Ó¡Ñ´ (Finite Set)  ¤×Í à«µ·ÕèÁըӹǹÊÁÒªÔ¡à·èҡѺ¨Ó¹Ç¹àµçÁºÇ¡ ËÃ×Í ÈÙ¹Âì àªè¹
  • ÁըӹǹÊÁÒªÔ¡à»ç¹ 0
  • {1, 2, 3, ...,100} ÁըӹǹÊÁÒªÔ¡à»ç¹ 100

  à«µÍ¹Ñ¹µì (Infinite Set)  ¤×Í à«µ·ÕèäÁèãªè૵¨Ó¡Ñ´ äÁèÊÒÁÒöºÍ¡¨Ó¹Ç¹ÊÁÒªÔ¡ä´é àªè¹
  • ૵¢Í§¨Ó¹Ç¹àµçÁºÇ¡ {1, 2, 3, ...}
  • ૵¢Í§¨Ø´º¹ÃйҺ

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  • ÊÑ­Åѡɳì ૵ A à·èҡѺ ૵ B á·¹´éÇ A = B
  • ૵ A äÁèà·èҡѺ ૵ B á·¹´éÇ A B

  à«µ·Õèà·Õºà·èҡѹ (Equivalentl Sets)  ¤×Í à«µ·ÕèÁըӹǹÊÁÒªÔ¡à·èҡѹ áÅÐÊÁÒªÔ¡¢Í§à«µ¨Ñº¤Ùè¡Ñ¹ä´é¾Í´ÕẺ˹Ö觵èÍ˹Öè§
  • ÊÑ­Åѡɳì ૵ A à·Õºà·èҡѺ ૵ B á·¹´éÇ A B

  ¡Ò÷Õè૵ A ¨Ðà»ç¹ÊѺ૵¢Í§à«µ B ä´é¹Ñé¹ÊÁÒªÔ¡·Ø¡µÑǢͧ૵ A ¨Ðµéͧà»ç¹ÊÁÒªÔ¡¢Í§à«µ B
ÊÑ­Åѡɳì ૵ A à»ç¹ÊѺ૵¢Í§à«µ B á·¹´éÇ A B
૵ A äÁèà»ç¹ÊѺ૵¢Í§à«µ B á·¹´éÇ A B


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1. ãªéÃÙ»ÊÕèàËÅÕèÂÁ¼×¹¼éÒËÃ×ÍÊÕèàËÅÕèÂÁÁØÁ©Ò¡á·¹àÍ¡À¾ÊÑÁ¾Ñ·¸ì
2. ãªéǧ¡ÅÁËÃ×ÍǧÃÕËÃ×ÍÃÙ»»Ô´ã´ æ ᷹૵µèÒ§ æ ·Õèà»ç¹ÊÁÒªÔ¡¢Í§ áÅÐà¢Õ¹ÀÒÂã¹ÊÕèàËÅÕèÂÁ¼×¹¼éÒ

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1. ÂÙà¹Õ¹ (Union) ÂÙà¹Õ¹¢Í§à«µ A áÅÐ B ¤×Í૵·Õè»ÃСͺ´éÇÂÊÁÒªÔ¡¢Í§à«µ A ËÃ×Í B à¢Õ¹᷹´éÇ A B
2. ÍÔ¹àµÍÃì૤ªÑ¹ (Intersection) ÍÔ¹àµÍÃì૤ªÑ¹¢Í§à«µ A áÅÐ B ¤×Í૵·Õè»ÃСͺ´éÇÂÊÁÒªÔ¡¢Í§à«µ A áÅÐ B à¢Õ¹᷹´éÇ A B
3. ¤ÍÁ¾ÅÕàÁ¹µì (Complement) ¤ÍÁ¾ÅÕàÁ¹µì¢Í§à«µ A ¤×Í૵·Õè»ÃСͺ´éÇÂÊÁÒªÔ¡·Õèà»ç¹ÊÁÒªÔ¡¢Í§àÍ¡À¾ÊÑÁ¾Ñ·¸ì áµèäÁèà»ç¹ÊÁÒªÔ¡¢Í§ A à¢Õ¹᷹´éÇ A'
4. ¼ÅµèÒ§¢Í§à«µ (Difference) ¼ÅµèÒ§¢Í§à«µ A áÅÐ B ¤×Í૵·Õè»ÃСͺ´éÇÂÊÁÒªÔ¡·Õèà»ç¹ÊÁÒªÔ¡¢Í§à«µ A áµèäÁèà»ç¹ÊÁÒªÔ¡¢Í§à«µ B à¢Õ¹᷹´éÇ A - B