Division by zero is not defined.Here's why. The division symbol is a question,ie12/4means 'what number must I multiply 4 by to get 12?'and of course tha answer is 3 .What about12/0? What number must I multiply zero by to get 12? There is no such number,and that is why mathematicians say it is not defined.Interestingly,the problem of division by zero led to the development by Newton of differential calculus,but that's for another time.
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