How do you find all the asymptotes for (4+3x)/(6-12x)?

1 Answer
Jul 9, 2015

Vertical Asymptote: x=1/2
Horizontal asymtote: y=-1/4

Explanation:

The first one is the vertical asymptote found by setting the condition:
6-12x!=0 this is done to avoid a zero in the denominator (that cannot be evaluated) and gives you that must be x!=1/2

So the vertical line with equation x=1/2 will be an asymptote of your function (cannot be crossed by it).

The horizontal asymptote can be found observing the behaviour of your function for very big values of x by doing:

lim_(x->oo)((4+3x)/(6-12x)) this will tell you whether or not your function tends to get near to some value.

lim_(x->oo)((4+3x)/(6-12x))=lim_(x->oo)(x(4/x+3))/(6x(1/x-2))=
=lim_(x->oo)(cancel(x)(4/x+3))/(6cancel(x)(1/x-2))=-1/4

So basically your function when x becomes very large tends to become equal to -1/4 so you have a horizontal asymptote (representing the line near which your functions tends) given as:
y=-1/4

Graphically:
graph{(4+3x)/(6-12x) [-10, 10, -5, 5]}