Functions, Test MONDAY! (1 Viewer)

[Line|z0r]

Hi guys, I have a 2 unit maths test monday so I have been revising some of our chapters. I came across this FUNCTIONS question that I am having a lot of trouble with. The question asks that you sketch a rough diagram of what this equation is:

xy=4

Any help will be greatly appreciated!

 

[Rahul]

basic tips:
to find x-int, make y=0
to find y-int, make x=0
to test, put in a pair of value for x and y, to test whether the rough sketch is correct.

for xy=4, well you know that the shape of the graph is a hyperbola.

general for for a hyperbola, xy=c. if c is positive, then it will be in quadrant 1 and 3(top-right and bottom left). if c is negative, then the hyperbola will be in quadrant 2 and 4.

the answer for xy=4 is below, excuse the bad editing skills.

edit/ those funny looking things are meant to be 1's. also for hyperbola question you must show any two points. to find them just let x=1 or any other number and then find y.

 

[Line|z0r]

your a lifesaver, thanx mate

maybe you could also look at my other post in the Maths Extension thread...

 

[Rahul]

no problem.

will have a look....