# HELP: Stable sum and messurable space

#### Hummingbird25

Hi

I some need of urgent assistance to show the following:

$$m(\epsilon)$$ is stable under a countable sum.

Please can somebody explain this to me?

You Guys are my only hope !

Sincerely Yours Hummingbird25

Last edited:

#### AKG

Homework Helper
There really are such things as bad questions.

#### Hummingbird25

Excuse me ?

What do I need to rephrase ?

Sincerley Hummingbird

AKG said:
There really are such things as bad questions.

#### Hummingbird25

m is messure defined m: \epsilon \rightarrow R_+

where R_+ is the set for all positive real numbers !

Sincerley Yours
Hummingbird

#### StatusX

Homework Helper
What do you mean by "stable under a countable sum"?

#### Hummingbird25

StatusX said:
What do you mean by "stable under a countable sum"?
I was hoping that you could help define. I have an idear that its about a sequence of sets which \epsilon is defined upon, but I'm not sure.

Any idears ??

Sincerely

Hummingbird

#### StatusX

Homework Helper
What? Where did you get this question? Exactly what did it say? What you said in the last post made no sense.

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