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checkitagain
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What are the domain and range of the following:
(Note: It is a relation that is not a function.)



[itex]y^2(x^2 - 1) = x^4[/itex]
 
on Phys.org
Since there's no one to one correspondence between a value for x and a value for y, you have 2 different mappings (functions in their own right). y_1 (x) and y_2 (x) with the same maximal domain (R-{+-1}). y_1 is minus 1 times y_2, for any allowable value of x.
 
dextercioby said:
Since there's no one to one correspondence
between a value for x and a value for y, you have 2 different mappings
(functions in their own right). y_1 (x) and y_2 (x) with the

[itex]> >[/itex] same maximal domain (R-{+-1}). [itex]< <[/itex]

y_1 is minus 1 times y_2, for any allowable value of x.
.



I take it you are only addressing the domain . . . for now.


With your notation, does (R - {+-1}) mean [itex](-\infty, -1) \ \ \cup \ \ (-1, 1) \ \ \cup \ \ (1, \infty) \ ?[/itex]


Or, does it mean [itex](-\infty, -1) \ \ \cup \ \ (1, \infty) \ ?[/itex]



I am asking you for your clarification before I comment further on the
possible/alleged correctness of your take on it. (I want to comment,
but I am waiting on some more information.)
 
dextercioby said:
I was too lazy to write down the LaTex code, but here goes

[tex]\mathbb{R} - \{\pm 1\}[/tex].


What about x = -1/2 or x = 1/2, for instance?


Would those work or not?
 
dextercioby said:
No, y would be imaginary [itex]> > \ \ regarding \ \ x \ = -1/2 \ \ and \ \ x \ = 1/2 \ \ < < .[/itex]



checkitagain said:
(R - {+-1}) means [itex](-\infty, -1) \ \ \cup \ \ (-1, 1) \ \ \cup \ \ (1, \infty) \ ?[/itex]


Or, does it mean [itex](-\infty, -1) \ \ \cup \ \ (1, \infty) \ ?[/itex]

So, then, we must eliminate the first choice of interval notation
in the above quote box. Is the second choice of interval notation
in the quote box correct?


Can x = 0 give y as a real value or not?