I have samsung rv509 laptop.. my wifi is not working well... It is not getting connect.. i am using ubuntu 12.04 32 bit. i have installed brodcom driver too

Hi. You will have to give a littlebit more information in order to get help. What wireless card are you using. (Do not expect people to google your laptop type and find out). Posting the output of lspci would also help.

And please explain a bit more detailed what you mean by "not working well". This could be anything from "the wireless card is not recognized at all" to "the network connection is slower than I would have expected". Are you just failing to connect to networks or do you not see them in the first place?
So please explain were you run into issues, what they are, what error messages you are getting (if any) and so on...