點解0!=1???

0!=1???
!=1
0×1=1???
0=1???
0=1×?×?×?
0=1×0×0×0
!=1 ?=0
So,? only can be 0.
Checking :Sub !=1, ?=0 into the formulae.
0!=1???
0×1=1×0×0×0
0=0
So,! equal to 1 and ? equal to 0 is corrert.

2007-10-13 22:02:52 補充：
提醒:!=「鍵盆」上的l

2007-10-13 22:08:30 補充：
做數要用最簡單’s方法!!! ^^

2007-10-13 22:10:17 補充：
做數要用最簡單’s方法!!! ^^

hey first u have to know
　　　　　　　4! = 4 x 3 x 2 x 1


so
we also have

　　　　　　　4! = 4 x 3!

got it?

then
in general,
compare WITH
　　　　　　　4! = 4 x 3 x 2 x 1　　　and
　　　　　　　4! = 4 x 3!

＞　　　　　　n! = n x (n-1)!

if n = 1
the above formula becomes
　　　　　　　1! = 1 x 0!

To be consistent,

　　　　　　　0! = 1

hope i can give u a help
=]