Yes that should work the unified switch should be able to manage up to 24 AP (the unified switch and AP must be in the same subnet) a DHCP server will be required as static IP Address are not supported by the AP in managed mode. The AP do not need to bee physically connected to the Unified switch
I am sure your 3Com sales representative should be able to answer all the questiosn you may have.
Have a good weekend
POM