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checkitagain
Dec13-11, 06:11 PM
in interval notation?



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





(This is my own problem.)

berkeman
Dec13-11, 06:24 PM
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...

berkeman
Dec13-11, 06:26 PM
If you put the relation into the form y = f(x), then you can talk about the Domain and Range of that function...

Mark44
Dec13-11, 06:36 PM
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.

checkitagain
Dec13-11, 06:41 PM
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.

checkitagain
Dec13-11, 06:45 PM
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.

Mark44
Dec13-11, 06:49 PM
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?



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.

micromass
Dec13-11, 06:51 PM
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.