
Originally Posted by
ebaines
This reminds me of a math teacher I had who had dozens of "proofs" that 1 = -1, or 0 = 2, or some such. Whenever he made a mistake working a problem on the board he would try to show why his mistake wasn't really a mistake using another such "proof." Here are two - enjoy!
1. 1 ^2 = -1 ^2
2. Take the square root of both sides: sqrt (1^2) = sqrt (-1^2)
3. since sqrt(a^2)= sqrt(a): 1 = -1
QED
And another:
1. 1 = -1^2
2. log(1) = log (-1^2) = 2 x log(-1), from log(a^n) = n log(a)
3. log(1) = 0, so 0 = 2 x log(-1)
4. Divide through by 2: 0 = log(-1)
5. Since 0 = log(1): log(1) = log(-1)
6. If log(a) = log(b) then a = b, so: 1 = -1. QED