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**GOKILL****Member**- Registered: 2010-03-19
- Posts: 26

#1

Let R be a ring where

If (i) R is commutative and (ii) 1+1 and 1+1+1 have inverse in R (1 is unity in R), show that 1R1=1.

#2

True/False? Explain it!

Hahhahah1579xx.. Please Help me

I am the greatest magician this century!!!

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**jk22****Member**- Registered: 2010-06-14
- Posts: 33

Hi, nice to meet you.

for #1 could we write :

let c=0 :

let a=0 : , the square of any number is 0

-------

from

:right-multiply with a :

let a=1,

but since the square of b is 0 : , which can be written :

*Last edited by jk22 (2010-07-01 21:27:44)*

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**Ricky****Moderator**- Registered: 2005-12-04
- Posts: 3,791

Something is wrong with #2, the claimed generator for I isn't even in I.

"In the real world, this would be a problem. But in mathematics, we can just define a place where this problem doesn't exist. So we'll go ahead and do that now..."

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