Step by step
The question
Question: find the domain of f(x) = 1/x, + 5.
f(x) = 1x + 5
The domain is all the x's we can put in.
domain = the x's that can go in
1 Find where the bottom is 0
We can never divide by 0.
So the bottom can never be 0.
÷ 0: not allowed
The bottom is just x.
So x = 0 makes it 0.
x = 0
So the domain is all real numbers except 0: x ≠ 0.
x ≠ 0
2 See it on the graph
Draw the grid.
Here is the graph of f(x) = 1/x, + 5.
It never touches x = 0: that x can't go in.
3 Check
Let's check.
Put 0 in: the bottom is 0.
Not allowed.
x = 0: 10 = 10 not allowed
Let's look back.
First: find where the bottom is 0.
Then: see it on the graph.
Last: check.
Answer
x ≠ 0