Characteristic of R is a Divisor of |R| (Modern Algebra)

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Homework Statement


if R is a finite ring, then the characteristic of R is a divisor of | R |.


Homework Equations





The Attempt at a Solution


Can this be proven using lagrange's and char R is the subgroup and R is finite group, then the order of char R is a divisor order of R, and i use coset to show this? or am I completely off thanks
 
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FanofAFan said:

Homework Statement


if R is a finite ring, then the characteristic of R is a divisor of | R |.


Homework Equations





The Attempt at a Solution


Can this be proven using lagrange's and char R is the subgroup and R is finite group, then the order of char R is a divisor order of R, and i use coset to show this? or am I completely off thanks

That's pretty much it, yes. The ring R under addition is a group. The characteristic of R is the size of the subgroup of R.
 
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