Asymptotes incorrectly computed

phenrotay shared this problem 3 years ago
Not a Problem

Geogebra Classic 5.0.425.0-d

Detrmination of asymptotes is unreliable.

Hereafter some examples.

The asymptotes determined by Geogebra for the following functions are incorrect !

t(x) = sqrt(2x - 3) / sqrt(2x² - 3)

u(x) = sqrt(3x² - 2) / sqrt(2x + 1)

P. Henrotay

Comments (4)


I think that the problem is not related to the asymptotes themselves, but to the domain of each function, that is rarely acknowledged by a software. Try the same functions in wolfram alpha and you'll get the same results.

This is why extra asymptotes are shown.


directly from help

Asymptote( <Function> ) GeoGebra will attempt to find the asymptotes of the function and return them in a list. It may not find them all, for example vertical asymptotes of non-rational functions such as ln(x).


I think the asymptotes are right but the graphs are wrong. Strictly the graphs of these should be the same:

sqrt(2x - 3) / sqrt(2x² - 3)
sqrt((2x - 3) / (2x² - 3))

(but that's not something we'll be fixing)


Strictly the graphs of these should be the same: 

i am not accord. they have different domains like log(f(x))-log(g(x)) and log(f(x)/g(x)) or (-sqrt(x) + sqrt(x² - 2))² and x² + x - 2sqrt(x³ - 2x) - 2

first case: both positive

second case: both equal sign

our formulas for functions are true only in the intersection of the domains of the functions

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