Interval notation of function's domain question

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The domain of the function f(x) = √(x² - x - 6) / (x - 5) is determined by ensuring the expression under the square root is non-negative and that x is not equal to 5. The critical points from the quadratic equation x² - x - 6 = 0 are x = -2 and x = 3. The valid intervals for the domain are identified as (-∞, -2] ∪ [3, 5) ∪ (5, +∞). This can also be expressed as (-∞, -2] ∪ [3, +∞) excluding x = 5. The final domain in interval notation is confirmed as accurate.
late347
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Homework Statement


find domain
f(x)= ## \frac{\sqrt{x^2-x-6}}{x-5} ##

Homework Equations

The Attempt at a Solution


[/B]
Well, one sees that x ≠5 and then we further investigate the dividend portion where the under-the-root expression ≥ 0

We can graph the parabola, and find the zeroes. Then investigate the intervals and keep in mind also that x ≠ 5 for the original function.

I'm interested in how is this domain described in the interval notation for domain such as with the [ ] brackets

I confirmed by pen-and-paper results with wolfram alpha and the particular type of notation that wolfram alpha uses is as follows.

domain: { x ∈ ℝ : x>5 or 5>x≥3 or x≤-2}
 
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late347 said:

Homework Statement


find domain
f(x)= ## \frac{\sqrt{x^2-x-6}}{x-5} ##

Homework Equations

The Attempt at a Solution


[/B]
Well, one sees that x ≠5 and then we further investigate the dividend portion where the under-the-root expression ≥ 0

We can graph the parabola, and find the zeroes. Then investigate the intervals and keep in mind also that x ≠ 5 for the original function.

I'm interested in how is this domain described in the interval notation for domain such as with the [ ] brackets

I confirmed by pen-and-paper results with wolfram alpha and the particular type of notation that wolfram alpha uses is as follows.

domain: { x ∈ ℝ : x>5 or 5>x≥3 or x≤-2}

Domain: ##(- \infty,-2] \cup [3,5) \cup (5, +\infty)##

Or: ##(- \infty,-2] \cup [3,+\infty) - \{5\}##
 
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