|
ÊÁѤÃÊÁÒªÔ¡ | ¤ÙèÁ×Í¡ÒÃãªé | ÃÒª×èÍÊÁÒªÔ¡ | »¯Ô·Ô¹ | ¢éͤÇÒÁÇѹ¹Õé | ¤é¹ËÒ |
|
à¤Ã×èͧÁ×ͧ͢ËÑÇ¢éÍ | ¤é¹ËÒã¹ËÑÇ¢é͹Õé |
#1
|
||||
|
||||
ʹء¡ÑºµÑÇàÅ¢: ·È¹ÔÂÁ«éÓ
·È¹ÔÂÁ«éӢͧàÈÉÊèǹá·é·ÕèÁÕÊèǹà»ç¹ 9,99,999,9999, ...
$\frac{a}{9}$ = 0.aaaaaaaa.... àªè¹ $\frac{7}{9}$ = 0.777777.... $\frac{ab}{99}$ = 0.abababab.... àªè¹ $\frac{71}{99}$ = 0.71717171.... ¶éÒàÈÉÁÕËÅÑ¡¹éÍ¡ÇèÒÊèǹ ãËéàµÔÁ 0 ¢éҧ˹éÒ àªè¹ ¨Ò¡ 7 à»ç¹ 07 ¹Ñ蹤×Í $\frac{7}{99}$ = 0.07070707.... $\frac{abc}{999}$ = 0.abcabcabc.... àªè¹ $\frac{719}{999}$ = 0.719719719.... $\frac{abcd}{9999}$ = 0.abcdabcdabcd.... àªè¹ $\frac{7193}{9999}$ = 0.719371937193.... - ¶éÒà»ç¹àÈÉÊèǹà¡Ô¹ ãËé·Óà»ç¹¨Ó¹Ç¹¤ÅСè͹ àªè¹ $\frac{15}{9} = 1 \frac{6}{9} $ = 1.666666.... (äÁèãªè 1.55555... ¹Ð¤ÃѺ ) - ¶éÒÁÕÊèǹà»ç¹ 90, 900, 990,... ãËé·ÓãËéÍÂÙèã¹ÃÙ»Êèǹ 9,99,999,... àªè¹ $\frac{15}{90} = 1 \frac{6}{9} x \frac{1}{10} $ = 1.666666.../10 = 0.1666666... àªè¹ $\frac{15}{900} = 1 \frac{6}{9} x \frac{1}{100} $ = 1.66666666.../100 = 0.016666... 19 Á¡ÃÒ¤Á 2011 10:53 : ¢éͤÇÒÁ¹Õé¶Ù¡á¡éä¢áÅéÇ 1 ¤ÃÑé§, ¤ÃÑé§ÅèÒÊØ´â´Â¤Ø³ yellow |
#2
|
||||
|
||||
¢Íº¤Ø³¤ÃѺ
¤Ô´§èÒ´Õ
__________________
¤³ÔµÈÒʵÃì ¤×Í ÀÒÉÒÊÒ¡Å ¤³ÔµÈÒʵÃì ¤×Í ¤ÇÒÁÊǧÒÁ ¤³ÔµÈÒʵÃì ¤×Í ¤ÇÒÁ¨ÃÔ§ µÔ´µÒÁªÁ¤ÅÔ»ÇÕ´ÕâÍä´é·Õèhttp://www.youtube.com/user/poperKM |
|
|