9.999... reasons that .999... = 1

Point Nine Repeating Equals One!
9.999... reasons in 9.999... minutes.

Bonus points if you can name all 9.999... lords a-leaping.

Dear YouTube, wouldn't it be nice if I could include the full script with this video? A larger character limit would not be unreasonable.

• Category

  Education

[Urketadic]

OMG WHAT THE FUCK??

[TheCheungDan]

Check at the video length, it is 9.9999999999999999999999999999­99999999... mins!!!

[Houssein Montgomery]

10 minus 0.9 repeating is 9? That's only true if 0.9 repeating is actually 1, which is what you're trying to prove.You can't change 0.9 repeating to 1 in the middle of your proof.

[SoMeOnERokaz]

Most, if not all, of the greek paradoxes are solved with infinite series and calculus :P

[GoldenKingStudio]

Oh you mentioned it! Of course!

[GoldenKingStudio]

These proofs, especially # 7, remind me so much of ancient Greek division paradoxes, or modern day supertasks, where you break up a task into an infinite number of parts in order to say the task is impossible. Look them up and it will possibly shed some new information on this problem.

[th6936]

yeah you also have to have a leap of faith (limit) for this is be accurate, and that definitely was not in the video. The video did however reference calculus previously however she should have been a bit more clear.

[mmerlinmm]

Apologies. Commented before finishing video... Shame...

[mmerlinmm]

Vi Hart dear: You must read about surreal numbers. In the surreal numbers there is a number 1-epsilon distinct from 1 and well defined. Epsilon is a well defined 1/countable infinity. Check them out!

[MuffinsAPlenty]

Excellent idea! Thank you.

[OfcJ9]

How is .99999 = 1 without rounding?