Drawing functions (1 Viewer)

S1M0

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Hey guys, its me again, asking for more help.

Draw:

f(x) =

2x^2
-------------
x^2 - 9

f(x) =

x - 4
-------------
x - 2

I have SOME clue as to what these graphs would look like, but i'm clueless on how to go about solving them. I can basically determine what the asymptotes will be, but thats where it ends.

Some help would be appreciated, as always. Go.
 
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P

pLuvia

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Find stat points: let f'(x)=0
Find concavity: sub values from either side of the stat point or find the f''(x)
Find intercepts
Find the limit as x--> +- infinity
 

S1M0

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pLuvia said:
Find stat points: let f'(x)=0
Find concavity: sub values from either side of the stat point or find the f''(x)
Find intercepts
Find the limit as x--> +- infinity
Helpful, but i need more insight if i'm to understand this question.

Thanks so far though.
 
P

pLuvia

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S1M0 said:
Helpful, but i need more insight if i'm to understand this question.

Thanks so far though.
Have you learnt how to find stationary points yet? if not it'll be quite annoying.

If not, find the intercepts by letting x and y equal to zero. Then to find how the curve behaves, find the limit as x approaches to + and - infinity
 
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yeah you learn stat points and stuff in year 12.

SIM0, for the graphs, if you've got the assympotes, then youre pretty much there. you should have a general idea of what the graph should look like (im assuming you kno its the shape of a hyperbola, thats what youre graphing). but to make sure just plot some points and you should get a general shape.
 

S1M0

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watatank said:
yeah you learn stat points and stuff in year 12.

SIM0, for the graphs, if you've got the assympotes, then youre pretty much there. you should have a general idea of what the graph should look like (im assuming you kno its the shape of a hyperbola, thats what youre graphing). but to make sure just plot some points and you should get a general shape.
Oh ok. I tried doing it without plotting some points.

Alright, i'll see how i go with this. Thanks guys. :)
 

Faytle

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To graph a function, consider:

1. x and y intercepts (let x=0, y=0)
2. even or odd function, or neither
3. domain and range (range usually found subsequent to sketching the graph)
4. asymptotes and limits (x approaches +- infinity)

That should give you a good idea of what the function is going to look like. Then just plot some points to fix it into place and ta da!

Hope that helps a bit!
 

jb_nc

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lim (x-4)/(x-2)
x-> +inf
 

S1M0

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Faytle said:
To graph a function, consider:

1. x and y intercepts (let x=0, y=0)
2. even or odd function, or neither
3. domain and range (range usually found subsequent to sketching the graph)
4. asymptotes and limits (x approaches +- infinity)

That should give you a good idea of what the function is going to look like. Then just plot some points to fix it into place and ta da!

Hope that helps a bit!
Alright guys, i'm glad to say that i've got the hang of this!

Its fairly easy now, but i still need to plot points, which means i'm not 100% good at it. But yeah....

Anyways click here
 

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