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Math Help - domain question

  1. #1
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    domain question

    I have the problem
    Give the domain in interval notation for the function:
    f(x)=(x+1)/(sqrt(x-2))

    I think it's (3,inf) because it would have to be 3 or more to be real.
    But Mathway says (-inf,3) U (3,inf). If x was 2 it would be imaginary, so what's the deal with Mathway?

    Thanks.
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  2. #2
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    Quote Originally Posted by dwatkins741 View Post
    I have the problem
    Give the domain in interval notation for the function:
    f(x)=(x+1)/(sqrt(x-2))

    I think it's (3,inf) because it would have to be 3 or more to be real.
    But Mathway says (-inf,3) U (3,inf). If x was 2 it would be imaginary, so what's the deal with Mathway?

    Thanks.
    sure you posted f(x) correctly? ... for the function posted

    x-2 > 0

    x > 2 ... domain.

    what's a "Mathway" ?
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  3. #3
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    Ok

    Yes, that was the problem. I see, it is x>2. Is that really in interval notation? I was trying to give it the form: (z,t)

    Mathway is a math help website that solves problems using software built in to the web page. I don't know if I trust it yet.
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  4. #4
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    x > 2 and (2,\infty) mean the same thing.
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