Question

Which of the following are AP? If they are in AP, find their first terms and common differences:
-5,-1,3,7,11​

Answer 1

Answer:

firstly we have to find, this is AP or not.

a1=-5 , a2=-1 , a3 = 7 and a4 = 11

d =a2-a1 = -1-(-5) = -1+5= 4

d= a3-a2 = 3-(-1) = 3+1 =4

d= a4-a3 = 11-7 = 4

As the difference between the terms are same, then this is AP.

the First term of AP is -5

and the common difference is 4