Los Angeles (KLAX) has a surprising gotcha when flying from an arrival and transitioning to an approach. You should be very aware and know that they will issue an approach clearance while still on the arrival. A terminating point on the arrival can also be the IAF on the approach. Trouble is, the assigned runway may not be issued to you until that point and you really need to scramble to punch into the FMS the correct approach. This can be a very high workload situation to those who are not expecting it and a few may even question its legality, but it is a perfectly acceptable clearance, though.
The above is intended to be advisory in nature and does not supersede any information contained in the FAR’s or AIM. Every situation is different and may not apply to every flight.