What are the asymptote(s) and hole(s), if any, of f(x) =(sqrt(3x)/(x-4))^3?

1 Answer
Mar 10, 2016

Asymptotes are x=4" and "y=0

Explanation:

Write as:" "f(x)=(3xsqrt(3x))/((x-4)^3)

color(blue)("Point 1")

We know that the function will be undefined as the denominator approaches zero.

Thus lim_(x->4) f(x) =lim_(x->4) (3xsqrt(3x))/((x-4)^3) -> (12sqrt(12))/0

color(blue)("This is undefined" => x=4 " is an asymptote")

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color(blue)("Point 2")

The denominator has x^3 as the most significant figure.
Whilst the numerators most significant figure is xsqrt(x)

Note that xsqrt(x) < x^3 so as the denominator 'grows' much faster
than the numerator lim_(x->+-oo) f(x)" tends to "0

color(blue)("Thus " y=0" is an asymptote")

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Tony B