Question

The sum of 'n' terms of an arithmetic sequence is 3n² +n. 19th term is how much more than 13th term ?​

Answer 1

Answer:

n=3n^2+n

Step-by-step explanation:

if we taken n=19 then n=3×19+19=76

so the 19th term=76

13th term=3×13+13=52

so the difference between 19th and 13th term =76-52

=24

19th term is 24 more than the 13th term

Answer 2

Answer:

36

Step-by-step explanation:

let the 1st term of ap be a

common difference be d

so

$sn = \frac{n}{2} \times (2a \: + (n - 1) d)$

substitute this to given term. then a little manipulation will give the answer