There are a lot of small features within Dynamics AX that can save you time and energy of trying to mentally calculate what you should do. One example of this is to do with entering in dates. If you have ever had to type in a date for the end of a month, and then had to pause to work out of the month has 28, 29, 30, or 31 days. Next time, just use the date of 31, and Dynamics AX will convert the date to the right value.
HOW TO DO IT
Type in your month end date with the date of 31.
HOW IT WORKS
Dynamics AX will update the date with the corrected date.