# A big controversy in math (0.999... = 1) **URL:** \ **Category:** Discussion\ **Created:** [April 23, 2026, 2:32am UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669 "2026-04-23T02:32:21Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![bhssingul](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/bhssingul/32/6761_2.png) [@bhssingul](https://cl.desmos.com/u/bhssingul)\ **Post date:** [April 30, 2026, 12:58pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/21 "2026-04-30T12:58:58Z")
well 0.99999=1means 1-1/infinity=1 from which -1/infinity=0 1/infinty=0 ---
**Author:** ![NTMDev](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/ntmdev/32/7141_2.png) [@NTMDev](https://cl.desmos.com/u/NTMDev)\ **Post date:** [April 30, 2026, 12:59pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/22 "2026-04-30T12:59:44Z")
I still don’t understand what 1/infinity is, you can’t use “infinity” in an operation Also the website you sent didn’t disprove anything, like the comment section said Also the website you sent was roasted by basically all the comments 😭 ---
**Author:** ![port](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/port/32/9839_2.png) [@port](https://cl.desmos.com/u/port)\ **Post date:** [May 15, 2026, 2:29pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/23 "2026-05-15T14:29:50Z")
uh .999… \* 10 is .999…0 ---
**Author:** ![port](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/port/32/9839_2.png) [@port](https://cl.desmos.com/u/port)\ **Post date:** [May 15, 2026, 2:31pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/24 "2026-05-15T14:31:45Z")
.000…1 can fit between them though ---
**Author:** ![port](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/port/32/9839_2.png) [@port](https://cl.desmos.com/u/port)\ **Post date:** [May 15, 2026, 2:33pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/25 "2026-05-15T14:33:01Z")
1/infty is a small nonzero number ---
**Author:** ![NTMDev](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/ntmdev/32/7141_2.png) [@NTMDev](https://cl.desmos.com/u/NTMDev)\ **Post date:** [May 19, 2026, 1:08pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/26 "2026-05-19T13:08:17Z")
No it’s not, you guys are actually annoying me so much. 1. Why do you care about the “0” at the end of a number? 2. Where are you putting this 0 if there are infinite 9s? ---
**Author:** ![NTMDev](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/ntmdev/32/7141_2.png) [@NTMDev](https://cl.desmos.com/u/NTMDev)\ **Post date:** [May 19, 2026, 1:09pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/27 "2026-05-19T13:09:39Z")
No, 1/infinity is 0, because in the first place, you can’t divide by infinity. Also, infinity isn’t even a number, so it makes no sense to divide a number by it, especially being in the denominator. It’s like arguing that “1/0” is “0”, but there is no meaning for “0” to be in the denominator. ---
**Author:** ![NTMDev](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/ntmdev/32/7141_2.png) [@NTMDev](https://cl.desmos.com/u/NTMDev)\ **Post date:** [May 19, 2026, 1:13pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/28 "2026-05-19T13:13:15Z")
Okay, so if I put `x/infinity` into a limit, does it progress towards 0 or infinity? ---
**Author:** ![NTMDev](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/ntmdev/32/7141_2.png) [@NTMDev](https://cl.desmos.com/u/NTMDev)\ **Post date:** [May 19, 2026, 1:16pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/29 "2026-05-19T13:16:27Z")
Okay none of these arguments make sense, I’m sorry lol How in the world did you get “-1/infinity=0” from “1-1/infinity=1”? > [@bhssingul](#): > > well 0.99999=1means 1-1/infinity=1 > from which > -1/infinity=0 > 1/infinty=0 ---
**Author:** ![port](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/port/32/9839_2.png) [@port](https://cl.desmos.com/u/port)\ **Post date:** [May 19, 2026, 5:15pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/30 "2026-05-19T17:15:25Z")
0, yet never reaches 0 ---
**Author:** ![NTMDev](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/ntmdev/32/7141_2.png) [@NTMDev](https://cl.desmos.com/u/NTMDev)\ **Post date:** [May 20, 2026, 1:58am UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/31 "2026-05-20T01:58:34Z")
Well no geometric sequence will ever converge according to your logic. That will break so many proofs. It is fundamental any limit converges or diverges, can’t be in the “never reaches” ---
**Author:** ![port](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/port/32/9839_2.png) [@port](https://cl.desmos.com/u/port)\ **Post date:** [May 20, 2026, 11:30am UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/32 "2026-05-20T11:30:30Z")
take the function 2^x for example. as x approaches negative infinity, y approaches 0, yet does not reach 0. ---
**Author:** ![Guzman\_Tierno](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/guzman_tierno/32/6149_2.png) [@Guzman\_Tierno](https://cl.desmos.com/u/Guzman_Tierno)\ **Post date:** [May 20, 2026, 1:54pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/33 "2026-05-20T13:54:45Z")
In math we define limits, the limit of 1/n as n goes to infinity is 0 and we write: lim 1/n = 0 which can be summarized as 1/inftinity = 0. ---
**Author:** ![port](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/port/32/9839_2.png) [@port](https://cl.desmos.com/u/port)\ **Post date:** [May 20, 2026, 1:56pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/34 "2026-05-20T13:56:15Z")
but say we have 2^x if x is negative 10, which is about 0.001. that is not zero. neither are other, smaller numbers ---
**Author:** ![NTMDev](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/ntmdev/32/7141_2.png) [@NTMDev](https://cl.desmos.com/u/NTMDev)\ **Post date:** [May 20, 2026, 2:07pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/35 "2026-05-20T14:07:37Z")
Okay but it is accepted that limits basically reach 0 or whatever number they converge to, and thanks for the explanation Guzman I was confused what he meant I did not know he was talking about limits or anything. ---
**Author:** ![port](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/port/32/9839_2.png) [@port](https://cl.desmos.com/u/port)\ **Post date:** [May 20, 2026, 2:09pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/36 "2026-05-20T14:09:22Z")
they _approach_ zero ---
**Author:** ![Guzman\_Tierno](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/guzman_tierno/32/6149_2.png) [@Guzman\_Tierno](https://cl.desmos.com/u/Guzman_Tierno)\ **Post date:** [May 20, 2026, 2:10pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/37 "2026-05-20T14:10:32Z")
Lim\_{x → -infinity} 2^x = 0 the values approach 0 … the limit IS 0. ---
**Author:** ![NTMDev](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/ntmdev/32/7141_2.png) [@NTMDev](https://cl.desmos.com/u/NTMDev)\ **Post date:** [May 20, 2026, 2:53pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/38 "2026-05-20T14:53:00Z")
Wait so now I’m confused. Does an infinite geometric sequence ever evaluate to something (_converge_), or does it just infinitely approach something? So is @port wrong? I think so…? ---
**Author:** ![Daniel\_Grubbs](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/daniel_grubbs/32/719_2.png) [@Daniel\_Grubbs](https://cl.desmos.com/u/Daniel_Grubbs)\ **Post date:** [May 20, 2026, 4:34pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/39 "2026-05-20T16:34:47Z")
From Wikipedia (with a reference), “In mathematics, a limit is the value that a function (or sequence) approaches as the argument (or index) approaches some value.” So when you say “converge” that is not necessarily a value that is reached. A simple example is one of Zeno’s paradoxes, which basically works off the ability to infinitely divide a distance in half. Say you’re traveling from one location to another, each day you travel halfway to your intended location. Day 1, you travel halfway. Day 2 you travel another quarter (half of the remaining half). Day 3 another eighth (half of the remaining quarter, etc. The sum of each day would be the series `1/2 + 1/4 + 1/8 + ...+ 1/2^n`. Because you keep halving the remaining distance, you would never actually reach a total of 1, but you approach it, so it converges on 1. ---
**Author:** ![NTMDev](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/ntmdev/32/7141_2.png) [@NTMDev](https://cl.desmos.com/u/NTMDev)\ **Post date:** [May 20, 2026, 5:21pm UTC](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669/40 "2026-05-20T17:21:54Z")
Well then 0.999… converges on 1? But how do we perform any operation on these types of number, that converge but don’t reach? That’s my question. I would believe that we just take that 0.999… = 1 because it gets infinitely close to 1 and you cannot define any gap between it. [Previous page](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669.md?page=1) [Next page](https://cl.desmos.com/t/a-big-controversy-in-math-0-999-1/8669.md?page=3)