[shiu1]

Provide a structure for the dibromo-product expected from the reaction of 1,2,3-
trimethylcyclohexene with Br2, and use this product to describe the difference between
the terms "absolute stereochemistry" and "relative stereochemistry".

[MissPhosgene]

Do you know what the product is?
Do you know the definitions of absolute and relative stereocontrol?

Think of the possibilities...

[shiu1]

is it going to be 1,2 dibromo 3-methylcyclohexane? i am not sure actually. i tried to look it up online but i am still really confused. please help !!!  

[Schrödinger]

Just Br₂ is quite vague. What are the exact reagents/conditions used?

[shiu1]

i don't know exactly cos that's what i got from my professor. it's something to do with bromination though. it should be something like the 1,2,3-trimethylcyclohexene forms a tertiary carbocation, then it got attacked from the backside by the bromide ion. can you still help me please??

[Schrödinger]

I guess we're in for an addition reaction across the double bond.
Carbocation...hmm.. i think a cyclic bromonium ion is formed, rather than a carbocation. The ring would block one side completely. So, bromide is free to attack only from the opposite side.

[shiu1]

so do u think 1,2 dibromo 3-methylcyclohexane will be the product?

[Schrödinger]

Yes, but you need to know the stereochemical aspects as well. I think you should google relative and absolute stereochemistry, or just look up your book for more details and better visualization