Concepts of A.P

So guys what is A.P:-

The full form of A.P is arithmetic progression the collection of the numbers.with a suitable relation is called A.P.

Term related with A.P:-

Let we take 3,6,9,12...

Here 3 is first term of A.P so we denote it with a so a=3

a2=6

a3=9

So guys we denote the nth term with 

An=a+(n-1)×d

Guys here is a new term d

Here d is common difference.

Means a2-a=d

Thus a3-a2=d

Here 6-3=3

9-6=3

So guys we can say that a collection of no. Is a.p if the difference between every term is same and this difference is called d or common difference

Here d=5 same for all

Let we take example 1,4,6,9

This is not A.P bcz here a2-a=3=d

a3-a2=6-4=2

Here we can see that the common difference is not same this is not a A.P.

Let we take another example
-3,-5,-7,-9....
Here we find d=-2
d=-7+5=-2
So here common difference is same so this is a A.P