A Derivation in Combinatory Categorial Grammer I am reading about CCG on page 23 of Speech and Language processing. There is a derivation as follows:

(VP/PP)/NP , VP\((VP/PP)/NP) =&gt; VP?


Can anyone example this please? This make sense if 

VP\((VP/PP)/NP) is equivalent to (VP\(VP/PP))/NP 


and 

(VP/PP)/NP is equivalent to VP/(PP/NP). 


But they seem at least non-trivial from the text!

Any help would be greatly appreciated.

CS
I guess I got it. It is simply: 

(X/Y)(Z\(X/Y)) which Z. 


In the example, 

X = VP/PP, Y = NP, and Z = VP.