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Domain of sqrt(2x^2-7)?

How I find the domain of √(2x2-7)? Please include all steps so I know what I'm doing, because I have no idea how to find the answer. Thanks!

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Vivian L. | Microsoft Word/Excel/Outlook, essay composition, math; I LOVE TO TEACHMicrosoft Word/Excel/Outlook, essay comp...
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Hi again M;
As you already know, we cannot square root anything less than zero.  We therefore must find the minimum value of 2x2-7
-√3.5≥x  Note the fact that because I multiplied the figure by a negative sign, I had to reverse the less than to greater than signage.
domain is (-∞, -√3.5]U[√3.5, +∞)


Would the domain also include (-√3.5, √3.5) because it could also be any of the values in between and be a real number?
I just updated my )(, parentheses, to ][, brackets, because I realized the same thing.
We cannot render the equation less than zero.  The values between these numbers are NOT included in the domain.
Oh yes, I just realized that. Even though it's negative and positive, there won't be anything in between because it won't fit the sign.