Assignment 2 woes

Hello

Please can someone give me some direction wrt assignment 2.
I completed question 1, tested it againt the different worlds, and fixed it up nicely. Feeling confident. Moved onto question 2.1, sorted it out. Got to question 2.2 and spend HOURS without making progress. Don't know if my strategy is right, but I need to know how to prove A->B and B->C as premises, can move to A->C. The book talks about this on page 200, but doesn't give it formally (that I can find). Looked at the link in a different posting, but not much help. Although I can see what I'm trying to do, I can't actually fet Fitch to accept my reasons for the steps.
PLEASE!!! Anything appreciated.

Thanks
Shaun

I am trying to prove the following, but my final step is giving me issues. Can someone please tell me how to link step 6 in?
Thanks

|1. A->B->B
-
||2. A
__
||3. B->C (Elim 1,2)
|||4. B
___
||| 5.C (Elim 3,4)
||6. A->C (Intro ???)

you don't need step 3.
B follows straight from 2, beacuse of Rule Elim ( premise A->B, and A (step2)
try it, then
just show how
B->C and C-> D ..(also elim rules.. then theres 2 more little elim steps
and you will have your a -> D

Thanks Iva

Will try it tonight. Actually made a mistake in typing out above. Should have premise A->B->C (not A->B->

ok cool, mail me if u stuggling as i might not be on teh forum

This is my code for trying to prove A -> C from the premise A -> (B -> C)

|1. A -> (B -> C)
-
||2. A
-
||3. B -> C (-> ELIM 1,2)
|||4. B
-
|||5. C (-> ELIM 3,4)
||6. C (-> ELIM 1,2,3,4-5)
|7. A -> C (-> INTRO 2,3)

When I verify the proof, all the steps get ticked, except step 6, step 2 & 4 are assumptions.

My problem is trying to bring a result to a lower level in the proof.

Iva, I didn't know your email address, mine is shaunv@pdc.co.za if maybe you can help me, or anyone else.

Thanks