Question

8 th term 12 12 th term 8 find the algebraic expression for the arithmetic sequence? very very urgent​

Answer 1

Answer:

T8=a+7d =12

T12=a+11d =8

T12-T8= 4d= -4

d=-1

a=12-7d =12-7×-1=19

First term is 19

Common difference is --1

Sequence is

19 18 17 16 15 ---

Tn= 19 +(n-1)(-1) =19-n+1=20-n

Tn =20-n