# Algebraic Function Question (1 Viewer)

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1. The problem statement, all variables and given/known data

Find the Domain

f(x) = ___2___
x+3

2. Relevant equations

3. The attempt at a solution I know this is a pretty simple question just want to make sure I'm on the right track. Wouldn't the domain be all numbers except zero? Because you can't divide by zero? How would I write this

#### Mark44

Mentor
1. The problem statement, all variables and given/known data

Find the Domain

f(x) = ___2___
x+3
Another way to write this that is clearer is f(x) = 2/(x + 3)
3. The attempt at a solution I know this is a pretty simple question just want to make sure I'm on the right track. Wouldn't the domain be all numbers except zero? Because you can't divide by zero? How would I write this
No, 0 is in the domain, because f(0) = 2/(0 + 3) = 2/3.
Yes, you cannot divide by zero. What value of x makes the denominator 0?

Well a -3 would make the denominator 0...

#### Mark44

Mentor
So -3 is not in the domain. Are there any other values for which this function is undefined?

#### cyby

What you are looking for is for the *denominator* to not be zero, such that you don't divide by zero. And you're right in saying that -3 is not in the domain. Just make sure that -3 is the only thing that's not in the domain.

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