.999999 = 1
Thread Starter
Floppy Death! noES!!!
Joined: Oct 2002
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From: Scranton, PA
Originally Posted by Buyimports2
What part of the guy's algebra is wrong? How did your teacher disprove this?
snitches get stitches
Joined: May 2002
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From: Portland, OR
Originally Posted by clickwir
Does someone need to write some big long equation just to show you that 2+2=4 or to show you that 3 + 3 = 4523465 is wrong? No, it just is. There is no need to show any proof, it just is wrong.
Therein lies the problem with proving something so inherently simple.
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Originally Posted by clickwir
Yes 1/3 = .33333 repeating. It equals that because 1/3 cannot be completely expressed in decimal form. You can't write 1/3 in decimal form and be 100% accurate. .33 repeating is not 1/3, it's as close as any number can get to being 1/3. But that doesn't mean it is 1/3.
How do you explain though his algebra when he subtracts x=9 from 10x=9.999999 ? I can't figure out a way to disprove that one.
snitches get stitches
Joined: May 2002
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From: Portland, OR
Originally Posted by Buyimports2
Very interesting point.
How do you explain though his algebra when he subtracts x=9 from 10x=9.999999 ? I can't figure out a way to disprove that one.
How do you explain though his algebra when he subtracts x=9 from 10x=9.999999 ? I can't figure out a way to disprove that one.
Its all rounding error. His whole argument is based on rounding error.
Pic Whore
Joined: Jul 2004
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From: NJ
Originally Posted by Buyimports2
Very interesting point.
How do you explain though his algebra when he subtracts x=9 from 10x=9.999999 ? I can't figure out a way to disprove that one.
How do you explain though his algebra when he subtracts x=9 from 10x=9.999999 ? I can't figure out a way to disprove that one.
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From: Montréal, Canada
Originally Posted by clickwir
Fractions and decimals are not always equal.
That's the single biggest flaw in his whole explination.
Yes 1/3 = .33333 repeating. It equals that because 1/3 cannot be completely expressed in decimal form. You can't write 1/3 in decimal form and be 100% accurate. .33 repeating is not 1/3, it's as close as any number can get to being 1/3. But that doesn't mean it is 1/3.
Same with 2/3 and same with .9999 repeating. Yes it is the closest you can get to 1, but it is not 1.
Assumptions and rounding does not equal accurate. Therefore, .999 repeating does not equal 1.
That's the single biggest flaw in his whole explination.
Yes 1/3 = .33333 repeating. It equals that because 1/3 cannot be completely expressed in decimal form. You can't write 1/3 in decimal form and be 100% accurate. .33 repeating is not 1/3, it's as close as any number can get to being 1/3. But that doesn't mean it is 1/3.
Same with 2/3 and same with .9999 repeating. Yes it is the closest you can get to 1, but it is not 1.
Assumptions and rounding does not equal accurate. Therefore, .999 repeating does not equal 1.
Thread Starter
Floppy Death! noES!!!
Joined: Oct 2002
Posts: 21,218
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From: Scranton, PA
Originally Posted by Buyimports2
Very interesting point.
How do you explain though his algebra when he subtracts x=9 from 10x=9.999999 ? I can't figure out a way to disprove that one.
How do you explain though his algebra when he subtracts x=9 from 10x=9.999999 ? I can't figure out a way to disprove that one.
He could come up with some 5 page formula to try an show that he has a point, but the only point is that he's wrong. .999 repeating is a theoretical number and cannot equal any other number other than itself. It doesn't equal .998 repeating jsut cause it's close. It doens't equal 2, because .999 repeating has high values. It doesn't equal 1 because it is simply a diffrent number.
You don't even have to use math to disprove it. A 3 year old can look at these 2 numbers and tell you they are not the same. 1 is not equal to 2. Anyone with basic comparison skills can tell you that. Just because he uses some mumbojumbo to try and hide that he's rounding, doesn't change things. He's trying to show that rounding numbers is the same as unrounded numbers. If that were the case then we wouldn't have either because they would be one in the same.