Question

What is the sum of the 7th and 15th term of the arithmetic sequence 2, 8, 14, ... ?

Answer 1

Explanation:

If we look at sequence,

a1=2 and a2=8

So,

d=a2-a1=8-2=6

And we know the formula for arithmetic sequence is

`a_n=a_1+(n-1)*d`

hence 7th term would be a_7=2+(7-1)*6=>
`a_7=38`

and a_15=2+(15-1)*6=>
`a_1_5=86`