You use explicit funtion to find a particular number in the list without needing to write all the list down. For example, the first range of number has a constant difference of 5. Its explicit funtion would be: x(n)=3+(n-1)*5 (with x is the number you need to find, n is the number's position in the range) Basically, a explicit funtion in that problem has the form: x(n)=f+(n-1)*d with: x= the number needed to find n= the number's position f = the first number in the range d = the distance Good luck!
