MHB S5.t.5 Find domain and asymptotes.

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The discussion focuses on finding the domain and asymptotes of the function g(x) = (2x^2 - 14x + 24) / (x^2 + 6x - 40). The domain is all real numbers except x = 4 and x = -10, expressed as x ∈ (-∞, -10) ∪ (-10, 4) ∪ (4, ∞). The horizontal asymptote is determined to be y = 2, while the vertical asymptote occurs at x = -10. There is also a mention of a removable discontinuity at x = 4, although it was not explicitly requested. The discussion touches on the conditions for oblique asymptotes but does not reach a conclusion on their presence.
karush
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$\tiny{s5.t.5 Kiaser HS}$
Find domain asymptotes.
$g(x)=\dfrac{2x^2-14x+24}{x^2+6x-40}$
$\begin{array}{rll}
\textsf{factor}&=\dfrac{2(x-3)(x-4)}{(x-4)(x+10)}
=\dfrac{2(x-3)\cancel{(x-4)}}{\cancel{(x-4)}(x+10)}
=\dfrac{2(x-3)}{x+10}\\
\textsf{Domain} & -\infty<-10<\infty\\
HA \quad y&=3 \\
VA \quad x&=-10
\end{array}$
I think there is an oblique asymptote but ??
Also the OP has a hole at $x=4$ but they didn't ask for it ?

btw how come tab does not work here?:confused:
 
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what does $-\infty < -10 < \infty$ mean?
the domain is all reals except x = 4 and x = -10 …
$x \in (-\infty, -10) \cup (-10,4) \cup (4, \infty)$

horizontal asymptote is y = 2

oblique asymptotes occur when the degree of the numerator is one greater than the degree of the denominator

yes, the original rational function has a removable discontinuity at x = 4
 
how do you get y=2 for HA
 
karush said:
how do you get y=2 for HA

$\displaystyle \lim_{x \to \pm \infty} \dfrac{2x^2-14x+24}{x^2+6x-40}$
 
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