The following work shows that for any two equal numbers a and b, we have 1 = 2. What is wrong in the work?
a = b , ab = b2 , ab-a2 = b2-a2 , a(b-a) - (b+a)(b-a) , a = b+a , a = b+b , a =2b , b = 2b , 1 = 2
更新1:
係吾係有D亂呀？因為吾知why我的電腦一打到ab-a2 = b2-a2就打吾到，如果看不明，只要把上面的數字直寫就可以． e.g. a=b ab=b2 ab-a2=b2-a2 ...