Question

if sum of n terms of an AP is given by 5n^2+8n, find its nth term.

Answer 1

Answer:

Answer: Step-by-step explanation: Let an denotes the nth terms and Sn denotes the sum of the first n terms ofgiven AP. Hence, the nth term ( an) = 10n +7 & the common Difference is 10.

Answer 2

Answer:

for n=1,we get 1st term

so 1st term is 5+8=13

for n=2,we get sum of 1st and 2nd term

=5.4+8.2=36

so common difference is

36-2.13=36-26=10

nth term = 13 +(n-1).10

=13+10n-10=10n+3