Finding related functional dependencies from Amstrong's axioms Let be 

F = { AB → C,
       B → D,
      CD → E,
      CE → GH,
       G → A }


some functional dependencies.

Do we have, thanks to Amstrong's axioms or its corollaries AB → G?

My attempt

I don't think so because

AB → C
CE → GH


Then from the pseudo-transitivity rule:


  {X → Y, WY → Z}⊨XW → Z


Then 

ABE → GH


And tht's all. We can't get rid of H.
This is rather easy. 

AB → C
B → D

therefore:

AB → C
AB → D

and:

AB → CD


Next:

AB → CD
CD → E

therefore:

AB → E

with: AB → C
we get:

AB → CE


And finally:

CE → GH

thus:

CE → G

and with the (previous): AB → CE

AB → G