Domain of a Function

frichar3

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Sep 12, 2005
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The domain of the function :Square root over (13x divided by xsquared-4)....I dont knwo how to write it with the signs and all. Use interval notation[/code]
 
I'm going to guess that the instructions are "Find the domain of the following function, and state your answer using interval notation." But I'm afraid I can't guess what the function is supposed to be...?

To format a square root, use the "sqrt()" notation, using grouping symbols to make your meaning clear. For instance, "the square root of nine equals three" would look like "sqrt(9) = 3", and "the square root of the sum of x<sup>2</sup> and four" would look like "sqrt(x<sup>2</sup> + 4)".

Thank you.

Eliz.
 
Yes and the function is sqrt(13x/(x^2-4) I hope this makes better sense to you ...again I get the "wrong" answer
 
So the function is:

. . . . .sqrt[(13x)/(x<sup>2</sup> - 4)]

The domain is all allowable x-values. Can you have a zero in the denominator? So throw out all x-values that make the denominator zero. Can you have a negative inside a square root? So throw out all x-values that make (13x)/(x<sup>2</sup> - 4) negative.

What have you done? What answer did you get? What answer is "right"?

Eliz.
 
i took the equation sqrt[(13x)/(x2 - 4)] greater than or equal to 0.
I put the quation on my grapher and ended up with [-2,0] U [3,infinity] Could it be my brackets? shoudl they be soft()?
 
Can you divide by zero? Is "infinity" a number that can be "included" in an interval?

Eliz.
 
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