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General - 0.999....=1 - View Post

MohammadBadir said:
It's kinda hard to grasp. On one hand 0.33333 = 1/3 so 0.99999 should be 1, but on the other hand, it stars with 0 so it's technically an infinitesimal smaller :P

It's not. Decimal notation with the "..." at the end (or a bar over the repeating part) is actually shorthand for a mathematical limit. What 0.999999... actually represents is

sum from n=1 to infinity of 9/(10^n)

And that evaluates to 1. The fact that it "starts with zero" is irrelevant. Decimal notation is nothing more than a representation, it's not actually a number. 0.1111.... represents 1/9. 0.9999.... represents 1.