# B Is 0.99.. Equal 1

#### Astro021

I want to see a proof why 0.999999... Is not equal 1 or why is it

#### PeroK

Science Advisor
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I want to see a proof why 0.999999... Is not equal 1 or why is it
There must be dozens of threads on here covering this.

The short answer is that $0.999 \dots$ is defined as an infinite geometric series, whose sum equals $1$.

#### mfb

Mentor
The internet is full of proofs that it is 1.

A couple of older threads here:
1, 2, 3, 4, ...

No need to repeat this again. I closed the thread.

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"Is 0.99.. Equal 1"

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