一個自己想的數學題

orb

326^2 - 325^2 = ?

要有一個快速計算的reason (知道的可在10秒內計算)

比超仔

我知la
651=.=
325+326-.-

幻藍

Originally posted by eeEric at 2005-5-5 07:20 PM:
326^2 - 325^2 = ?

要有一個快速計算的reason (知道的可在10秒內計算)

326^2-325^2
=(326+325)(326-325)
=651

snoopy11hk

...well done....
=(a-b)(a+b)....

me .... 99 (square)

細薯

只出一題.....
俾人做左就冇野玩 la .......><

orb

Originally posted by smallpotato226 at 2005/5/6 04:26 PM:
只出一題.....
俾人做左就冇野玩 la .......><

重點是reason

(很多人都沒有說為甚麼咁計...)

細薯

Originally posted by eeEric at 2005-5-6 04:33 PM:


重點是reason

(很多人都沒有說為甚麼咁計...)

a^2 - b^2 = (a + b)(a - b)

太易咪ng講lor~~

snoopy11hk

...有 ar....

99 *99

oscar

其實樓主條題目...我最多2秒已經計好...

[ Last edited by oscar on 2005-5-6 at 08:40 PM ]

幻藍

Originally posted by snoopy11hk at 2005-5-6 05:14 PM:
...有 ar....

99 *99

99x99
=98x100+1
=9801

[ Last edited by 可愛的兔兒 on 2005-5-6 at 09:41 PM ]