[ 3 / biz / cgl / ck / diy / fa / ic / jp / lit / sci / vr / vt ] [ index / top / reports ] [ become a patron ] [ status ]
2023-11: Warosu is now out of extended maintenance.

/sci/ - Science & Math

View post   
File: 106 KB, 953x613, 1297529544462.jpg [View same] [iqdb] [saucenao] [google]
2753893 No.2753893 [Reply] [Original]

...

>> No.2753910

>replyan to a troll thread

That "proof by induction" is wrong. Saying 0.9..*10=9.9... requires a proof, which ends up being exactly the same proof that 0.9...=10, save for a factor of 10.

>> No.2753953

>>2753910

What proof? You shift everything along by one place. The reason you're not left with an erroneous empty decimal column is because there is always another 9 to fill the empty spot due to it being an infinite recurring decimal. Bam, Q.E.D.

>> No.2754037

x = .999...
10x= 9.999...
10x-x= 9.999... - .999...
9x=9 <========= this is a separate equation with a new unknown.....
hurr


x=.5
2x=1
5x-x=2
2x=2
x=1 <====

>> No.2754075

>>2754037
>x=0.5
>5x-x=2
> implying 5x-x=2x

No, 5x-x = 4x =2
x=2/4
x=0.5
Nice try though.

>> No.2754101

>>2754037
lol no

>> No.2754104

>>2754075
5x-x
5(.5) - (.5)=
2.5 - (.5)=2

>> No.2754126

>>2754037
the left side is 10x - x, which is by the distributive property the same as (10 - 1)x = 9x
The right side is 9.999... - 0.999.. which is kind of obviously equal to 9.

If you don't like it, fuck off. It's a trivial matter anyway and only retards get worked up over it.

>> No.2754153

>9x=9 <========= this is a separate equation with a new unknown.....
dude hasn't heard of logical implication...

>> No.2754166

>>2754126
x= .999...
(10 - 1)x = 9x
9x=9x

not proof for x=1

>> No.2754184

>>2754166
lolwut

>> No.2754185

>>2754166
0/10. Try harder.

The right side isn't 9x. You intentionally left steps out to hide your troll bullshit a little better, but consider this:
at this very moment there are guys out there fucking beautiful girls while you try to troll neckbeards on /sci/.
How does this make you feel?

>> No.2754226
File: 30 KB, 675x1127, ZeroPointNine.png [View same] [iqdb] [saucenao] [google]
2754226

This is a version that's slightly more rigorous, but impossible to argue against.

BTW the entire last 2/3rds of the image isn't even necessary, but it's there for completion's sake.

>> No.2754228

>>2754185
(10 - 1)x = 9x

just said x=.9999
9x=?
9(.999)=who cares its still not proof

>> No.2754231

>>2753953

Sure, thats an "intuitive" argument, but intuitive arguments hold absolutely zero weight in mathematics.