Question

sum of first n terms of a series 5nsq + 2n find the second term of this series

Answer 1

Answer:

2nd term = 17

Step-by-step explanation:

sum of n terms

$5 {n}^{2} + 2n \\ first \: term \:a1 = s1 = 5( {1)}^{2} + 2(1) \\ = 5 + 2 = 7 \\ sum \: of \: 2 \: terms \\ s2 = 5( {2)}^{2} + 2(2) \\ = 5 \times 4 + 2 \times 2 \\ = 20 + 4 \\ = 24$

s2 = a1 + a2

24 = 7 + a2

a2 = 24 - 7

a2 = 17

second term of the series is 17

hope you get your answer