Year 12s: what will be the first way you research your future options? >>

Stuck on drawing a graph (reciprocals)

Hey guys.

So I have to sketch the graph and find the points of intersect.

The graphs are g(x) =-1 and f(x) = 3/x^2 - 4/x ( where x is not 0 )

This is edexcel pure maths year 12 btw. I did the exercise on reciprocals but I have no idea how to draw this and how to work out the roots or anything. So confused on how to draw it.

Working out the points of intersects is calm , but drawing the reciprocal? help pls

bumpedty bump bump

mandems help me

Hey,

Do you understand this part?
Making both equations equal then multiplying by x cubed as you must make all values have x so by multiplying by x cubed, 3/x^2 becomes 3x and you then have to multiply the rest also by x cubed.

Reply 4

the bear

you can remind yourself of what the graphs of 1/x and 1/x² look like here:

http://fooplot.com

Reply 5

Notnek

Hi, try not to bump your threads. Honestly you'll get a reply quicker if you leave your thread unanswered. If you bump your thread then it will look like someone has alredy replied to you :smile:

Reply 6

username2975726

Original post by TheArabEconomist

ahhh ok

tysm

Original post by Notnek

Hi, try not to bump your threads. Honestly you'll get a reply quicker if you leave your thread unanswered. If you bump your thread then it will look like someone has alredy replied to you :smile:

Didn't realise that sorry :tongue:

Reply 7

haarithiop

It's certainly not obvious how to draw it so I would consider a few things:

1. Where does the curve cross the x axis (i.e. y=0) and what happens when x is 0
2. Identify any asymptotes and consider what happens when x is +/- infinity
3. Finally find any stationary points (maxima/minima)