How to find range? f(x)=x^2/1-x^2
I know the answer but I need to understand how to do it.
There's actually no fixed method or algorithm for finding the range. You usually do it using the domain, so first find the domain.
Domain: \[(-\infty,-1) \cup(-1,1)\cup(1,\infty)\] \[x \neq1,-1\]
what now?
Yes that's the right domain. You can check to see if there's horizontal asymptotes. Check out this link: http://www.coolmath.com/precalculus-review-calculus-intro/precalculus-algebra/18-rational-functions-finding-horizontal-slant-asymptotes-01
The horizontal asymptote is -1?
Yes, it's y = -1
So all y-values will be defined for the graph except when y = -1.
Looking at a graph is always a good idea to help with finding range: https://www.google.com/search?q=x%5E2%2F1-x%5E2&oq=x%5E2%2F1-x%5E2&aqs=chrome..69i57&sourceid=chrome&ie=UTF-8#q=x%5E2%2F(1-x%5E2) (you can zoom in or out on google too)
Oh, so how would I write the answer? Like \[(-\infty,-1) \cup[0,\infty)\]
From the graph, that looks exactly right
okay cool. However, my text book answer page says that it is \[(-\infty,\infty)\cup[0,\infty)\]
is that the same thing?
That makes absolutely no sense as a range, haha the first part says the range is all real numbers, -infinity to infinity
I'd bet it was a mistake and the infinity should be -1
I agree. Thank you!
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