Question

It is always convenient to make a choice of
(i) 3 numbers in AP as (a -d), a, (a + d);
(ii) 4 numbers in AP as (a -3d), (a -d), (a +d), (a +3d);
(iii) 5 numbers in AP as (a - 2d), (a -d), a, (a + d), (a +2d).


please explain me this ​

Answer 1

Answer:

Yeah

Step-by-step explanation:

Lets hypothetically say for now that we have to add first 3 terms of an A.P.

But,you dont know the value of D

So,

If we use (a-d),(a),(a+d)

So,now we add it here

a-d+a+a+d=3a

//now we can easily find it without knowing the value of D

Thats it.........