Trouble graphing and working out functions

[Solidmozza]

Hi everyone.
Im on a bit of a time crunch, so all advice ASAP would be greatly appreciated.
Im usually quite good at maths, am In High School, and we are doing functions. In particular, I am having trouble graphing and working out functions like the following type:
Eg Graph the following, y = 1/(x*2+1)
or Graph the following, y = x + 1/x
Any help in a technique on how to do these types of problems, ASAP, would be greatly appreciated.
Thanks!

 

[moose]

If you get stuck, just make a t-chart :D
I'm totally serious though, if you ever forget how a certain graph looks, just plug in a few sample points.

 

[xanthym]

Hi everyone.
Im on a bit of a time crunch, so all advice ASAP would be greatly appreciated.
Im usually quite good at maths, am In High School, and we are doing functions. In particular, I am having trouble graphing and working out functions like the following type:
Eg Graph the following, y = 1/(x*2+1)
or Graph the following, y = x + 1/x
Any help in a technique on how to do these types of problems, ASAP, would be greatly appreciated.
Thanks!

Basic technique is to start with x-intercepts, y-intercepts, x-asymptotes, and y-asymptotes, and then fill in between by calculating and graphing some individual (x,y) point values (where needed until the graph seems complete). The first URL below presents a good review of this technique. The 2nd URL provides an on-line grapher from your browser to quickly graph most simple algebraic functions. (Instructions for its use are below the graph display.)
http://www.wiu.edu/users/mfjro1/wiu/tea/Functions/handouts/graphrat-howto.htm
http://www.math.niu.edu/~apel/applets/numericalAnalysis/graphingApplet/


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