2=-1 Unbelievable Math Proof
1. Let us consider any two equal non-zero quantities x and y.
x=y
2. Adding and subtracting x on left hand side of equation while adding and subtracting y on right hand side of the equation
x+x-x=y+y-y
3. Let us proceed as follows
2x-x=2y-y
2x-2y=-y+x
4. Taking 2 common from left hand side of equation and taking – common from right hand side of equation
2(x-y)=-(x-y)
5. Divide out by (x-y)
2=-1
Check it twice and try to pick out the mistake. You will not find any mistake because in mathematics there are some typical kind of mistakes difficult to pick out known as mathematical fallacies. The mistake actually is the division by zero, the very last step number 5. The division by (x-y), which is zero since x equals y. Since division by zero is undefined, the argument is invalid. A similar invalid proof would be to say that since 2 × 0 = 1 × 0 (which is true), one can divide by zero to obtain 2 = 1.
Math is just awesome and amazing sometimes. After all this I am in a very good position to say, “I LOVE MATHS”. You can find some more very interesting mathematical fallacies at Wikipedia. Here is the link to follow http://en.wikipedia.org/wiki/2=1. Hope you have enjoyed the proof. Show this to your teachers to puzzle them and make fun out of maths.
Written by abid ali qureshi
professional writer