Question

the nth term of an arithmetic progression is 15 - 7n find its common difference

Answer 1

u can find Its first term by putting n= 1
i.e.
15-7=8
2nd term =15-14=1

Hence Common difference is 2nd term-1st term
1-8=> -7


Got ittt

Answer 2

nth term = 15-7n
(n-1)th term =15-7(n-1) =22-7n
common difference
= nth term -(n-1)th term
=(15-7n)-(22-7n)=-7