引用:
Originally posted by sleepy
從別處看來的，題目是這樣：
假設a=b
=> a^2 = ab
=> a^2 - b^2 = a^2 - ab
=> (a + b)(a - b) = a^2 - ab
=> (a + b)(a - b) = a(a-b)
=> a + b = a
=> 2a = a
=> 2 = 1 
有人知道為何嗎？
a^2 : 表示a的平方
|
=> a^2 - b^2 = a^2 - ab=a^2-a^2=0 = ="
=> (a + b)(a - b)<---a=b那a-b=0,(a+b)*0=0 = ="
=> a + b = a<---應該等於2a吧 = ="
=> 2a =2a
=> 1 = 1 ............