No, you may not count the same expenses for the 529 plan distribution and the IRA withdrawal penalty exception*. But, since you say that the total qualified college expenses are greater than the IRA withdrawal and 529 distribution combined, this should not be a problem in your case.
*For example, if you make a $10,000 529 withdrawal and a $10,000 IRA withdrawal and only paid $18,000 in expenses, you will have to decide how the allocate the the $18,000 between the two tax breaks.
It gets more complicated, as you are probably claiming one of the education credits. You may NOT count the same expenses for a 529 plan withdrawal that your count for a tuition credit. But, you MAY count the same expenses for the IRA penalty exception that you count for a tuition credit.
