0A sequence is called an AP. If its terms continuously increase or decrease by the same number, this fixed number is called the common difference of the AP (d). Which can be positive or negative or zero. The first term of AP is denoted by 'a1', and the 2nd term is a2.....nth term is an.
Finite AP
An AP with finite no. Of terms is called finite AP
Infinite AP
An AP with infinite no. Of terms is called infinite AP
the nth term of an AP
an= a1+ (n-1)d
Eg: a10 = a1+(10-1)d
2,7,12...
a10=2+9×5
a10=47
