Today, we will recap the four basic rules of Differentiation:
- Differentiating Powers of x
(Power comes down, and the remaining power reduced by 1)
- Chain Rule (i.e. times differentiate inside the bracket)
- Product Rule
(Keep the first term X differentiate the second, PLUS keep the second term X differentiate the first)
- Quotient Rule
(Keep the bottom term differentiate the top MINUS keep the top differentiate the bottom, whole thing over )


denotes calendar year and the subscript
denotes quota year (May to April). Initially, projected deregistrations for (calendar) year
but from quota year 1999-2000 onwards, a projected number of deregistrations has been used.
percent growth in the total motor vehicle population, plus additional quota licenses to cover the number of motor vehicles that will be deregistered during the (calendar) year, plus any unallocated quota licenses from the previous quota year.