Traveled USA in B2 visa, can travel again for business (B1) with the same visa?

[World Traveler]

Hi there,
I have a valid B1/B2 visa. Two years back I had visited USA as a tourist with B2 marked in my US coustom and border protection stamp. Now I want to travel USA again for Bussiness trip (main reason) and then want to visit my brother too. Can I travel with the same visa? If yes, what possible documents I would have to present to the immigration officer in US entry port?
Suggestion would be appreciated. Thanks.

[jnk]

Yes you can use the same visa. You can show invitation letter from US Company and if visa officer ask you can inform after your business meeting will visit brother also. Be honest.