What are the domain and range of this relation

AI Thread Summary
The discussion revolves around finding the domain and range of the relation defined by the equation y^2(x^2 - 1) = x^4. Participants clarify that this relation cannot be expressed as a function, which complicates the determination of its domain and range. The equation can be rearranged to y^2 = x^4/(x^2 - 1), allowing for potential solutions for y. The original poster emphasizes that they are challenging others' understanding of domain and range rather than seeking a solution for a homework problem. The conversation highlights the distinction between relations and functions in the context of mathematical definitions.
checkitagain
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in interval notation?



y^2(x^2 - 1) = x^4





(This is my own problem.)
 
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checkitagain said:
in interval notation?



y^2(x^2 - 1) = x^4





(This is my own problem.)

Do you know the definition of Domain and Range of a function? Can you tell us what you think they are?

Then, is there anything that would inherently limit the domain of the function?

EDIT -- BTW, you haven't really defined a function yet. Domain and Range generally apply to a function...
 
If you put the relation into the form y = f(x), then you can talk about the Domain and Range of that function...
 
checkitagain said:
in interval notation?



y^2(x^2 - 1) = x^4





(This is my own problem.)

Your equation is equivalent to
y^2 = \frac{x^4}{x^2 - 1}
From this, you can solve for y.
 
berkeman said:
Do you know the definition of Domain and Range of a function? Can you tell us what you think they are?

Then, is there anything that would inherently limit the domain of the function?

EDIT -- BTW, you haven't really defined a function yet. Domain and Range generally apply to a function...


I am not trying to define a function. I know this is a relation
that is not a function.

And relations can have domains and ranges, as this one does.

In this problem I am challenging others with, I expect others to know
what the domain and range mean, but those aren't questions for me
in this particular problem.



One of many sources:

http://www.purplemath.com/modules/fcns2.htm

This relation can't be put into into a form y = f(x), because it isn't
a function to begin with.
 
Mark44 said:
Your equation is equivalent to
y^2 = \frac{x^4}{x^2 - 1}
From this, you can solve for y.

No, I am testing (read: challenging) users' knowledge
of domain and range to figure them out of this relation,
whether in my form or the equivalent form given by
Mark44.

I will be on at least a 90-minute break before returning
to this thread.
 
checkitagain said:
I am not trying to define a function. I know this is a relation
that is not a function.

And relations can have domains and ranges, as this one does.

In this problem I am challenging others with, I expect others to know
what the domain and range mean, but those aren't questions for me
in this particular problem.
It would have been helpful to include that information in your first post.

And that brings up a question: Since this isn't a question for you, why did you post it?
checkitagain said:
One of many sources:

http://www.purplemath.com/modules/fcns2.htm

This relation can't be put into into a form y = f(x), because it isn't
a function to begin with.
 
checkitagain said:
No, I am testing (read: challenging) users' knowledge
of domain and range to figure them out of this relation,
whether in my form or the equivalent form given by
Mark44.

I will be on at least a 90-minute break before returning
to this thread.

Since this is just testing of our knowledge, this means that this isn't a valid homework problem. So the thread can be locked.
 
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