Does .999999... = 1? - Topic

CPK001

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#91

Apr 14 2010 12:17am

3/3 is considered 1. Why should 0.999999999999999999999... not also be considered 1?

infinitesimal

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#92

Apr 14 2010 12:23am

Quote (CPK001 @ Apr 13 2010 11:17pm)

3/3 is considered 1. Why should 0.999999999999999999999... not also be considered 1?

Solid logic m8.

Hammer_Hdin

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#93

Apr 14 2010 06:11am

It's simple.
For every digit you add, you are putting it closer and closer to one.
But because infinity goes on forever, it is infinitely close to 1 which means it is one.

genuineretard

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#94

Apr 14 2010 06:13am

Yes it does equal 1.

rchau

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#95

Apr 14 2010 07:56am

Quote (Kahl4Prez @ Apr 11 2010 11:57am)

wow 2 people respond, and 2 people have a limited understanding of our mathematics...

what does 1/3 = ??????

ok now take 1/3 and x 3 = 1

1/3 = ????????

now multiply ????????? x 3 and what do u get?

.99999999...

there is my first fast proof...

you are right. .9999 is = 1.

Simplist proof:

1/3 = .33333
2/3 = .6666
3/3 = 1 not .99999999

you can do the same thing with 1/9.

.9999 is the same thing as 1.

xzpepijnzx

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#96

Apr 14 2010 08:03am

.9999 is not 1 because the answer to (c/(1-0.99999..) is finite.

kylo

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#97

Apr 14 2010 08:26am

Quote (xzpepijnzx @ Apr 14 2010 02:03pm)

.9999 is not 1 because the answer to (c/(1-0.99999..) is finite.

How so?

Kamikizzle

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#98

Apr 14 2010 10:36am

geometric series.
.999... = SUM(9/(10^n)) from n = 1 to inf
=9*SUM(1/10^n) = 9*[1/(1-(1/10))] = 1/(9/10)*9=[10/9]*9 = 10
10 - {the first term at n = 0}
=10 - 9
=1

get good son

xzpepijnzx

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#99

Apr 14 2010 10:57am

Quote (kylo @ 14 Apr 2010 16:26)

How so?