These are commutation functions, not used much any more in the SOA exams. Long ago (like back when I was taking the life contingencies exam) they were used a lot. Values by themselves really mean nothing, but ratios can be used for some calculations.
, not very useful. (where lx is from a standard life table, the number of people alive at age x; v is the normal interest function) Why you would want to calculate v^(number of people alive) seems incomprehensible, but the ratios actually turn out to be useful. Equally incomprehensible, why you would want v to that power times the number of people alive.
, not very useful.
That means (if you do the algebra / manipulation)
, and that is a useful thing to be able to calculate.
You can do other similar calculations from a single table of N's and D's. For example
is a 5-year deferred life annuity due on (x), and that is a useful thing to be able to calculate.
Your study material may have a section on commutation functions, or you could Google them.