0.999....=1

[Teeqoz]

JRPGfan said:

Faelco said:

 

0.999999 = 1 is wrong.

0.9999999.... = 1 is true. That 0.0000001 part doesn't exist with an infinity of 9.

 

It is basic mathematics, you can learn it in school (okay, it's more often teached as a "fun fact" in college or engineering schools), it's really well-known and established. 

You don't know how to prove that it is bad maths because it's not. You can find flaws in a demonstration of 0.99999.... = 1 but you will always find other ways to prove it, but not the contrary.

Example (I did'n't read the whole subject, sorry if already mentioned) :

1/3 = 0.333333333333...

3*(1/3) = 3*0.3333333333....

3*(1/3) = 1

3*0.3333333333333.... = 0.999999999999...

So 0.9999999999... = 1

Its just rounding it upwards.

It's not rounding. There is no use of rounding in the proofs present. They are exact, equal. Not rounded, almost, nearly.

there would be a infinite amount of 9s, but there would always also be a part missing.

 

The reason we can say 0.999999.... = 1 is because our minds cant comprehend infinity,

It's more like the other way around. The reason (some) people deny 0.999...=1 is because our minds can't comprehend infinity.