Oblique Asymtotes (1 Viewer)

DNETTZ

Camp-italist Fatcat
Joined
Jun 23, 2009
Messages
36
Gender
Undisclosed
HSC
2011
Right, was looking through for solving oblique asymtotes, and i was wondering how you do it through limits.
eg;
x+2
-----
x-1

Looks like this ;x+2/x-1 - Wolfram|Alpha
I dont like the long division method, it's dodgy. And it doesnt work here. This is fully simplified save (x+2)(X-1)^-1
Asymptotes: Comparing Graphs

So can someone tell me how?
 
Joined
Dec 31, 2009
Messages
4,741
Location
sarajevo
Gender
Female
HSC
2015
Uni Grad
2017
But... there aren't any oblique asymptotes, there is a horizontal one at y=1 and a vertical one at x=1...
 

kcqn93

Member
Joined
Jul 27, 2008
Messages
473
Gender
Male
HSC
2010
your input is wrong for the wolfram LOL

and yeh there isnt an oblique...
 

nonsenseTM

Member
Joined
May 29, 2009
Messages
151
Gender
Male
HSC
2010
if you meant (x+2)/(x-1) [add the bracket when using wolframalpha] , then it has

a vert. aymt. at x=1 cos x-1 can't be 0, consider limits-from 1+ve side (like 1.01+2/1.01-1) , it's +ve infinity , consider the other side of 1 (like 0.99+2/0.99-1), it's -ve infinity

a hor. asyt. at y=1 cos as x approaches inf. it's a reallly large no. divided by something a bit smaller than it (like 1000+2/1000-1), so it should be just more than 1
as x --> -ve infinity, x-1 becomes really large -ve no. which is to divide the slightly smaller x+2 (say -1000+2/-1000-1), y--> a bit less than 1

so it's like y=1/x shifted up 1 unit and right 1 unit
 
Last edited:

nonsenseTM

Member
Joined
May 29, 2009
Messages
151
Gender
Male
HSC
2010
if you wanna pracitce oblique asymtotes, try the one from adomad

it's best done by division which isn't quite "dodgy" and x^2+2/x+1=x+1+3/x+1

but don't worry too much about it , you're given things like x^2+2/x+1=x+1+3/x+1 and you only need to analyse the limits logically
 
Last edited:

DNETTZ

Camp-italist Fatcat
Joined
Jun 23, 2009
Messages
36
Gender
Undisclosed
HSC
2011
Yeah sorry about the misquote onto wolfram.
I got the limits method from wikipedia instead for forming a limit in y=mx+n which is what I was trying to do.
so its good now.
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top