Question

Find the 6th term of an arithmetic sequence given that a(1)= 12 and a(n)= a(n-1)-23

Answer 1

-103

Explanation:

a(1) = 12

a(n) = a(n-1) - 23

a(2) = a(1) - 23

= 12 - 23

= -11

Common difference (d) = a(2) -a(1) = -11 - 12 = -23

a(n) = a1 + (n-1)d

a(6) = 12 + 5 * (-23)

= 12 - 115

= -103