Question

write down in term of n an expression for the n th term of the following sequence a) 4,1,-2,-5,-8. b)-7,-12,-17,-22,-27​

Answer 1

Explanation:

a) a = 4; d =1-4 = -3

nth term = a + (n-1)*d

= 4 + (n-1) * -3 = 4 -3n +3

nth term =7 - 3n

b) a = -7; d = -12 - (-7) = -12 + 7 = -5

nth term = -7 + (n-1) * -5

= -7 - 5n + 5

= -2 - 5n