well, the first n terms of 2^(n-1) is 2^n - 1
The first n terms of 5n is 5 * n(n+1)/2
So, the sum you want is
2^n - 1 + 5n(n+1)/2
The nth term of a series is 2^n-1 +5n. Find the sum of the first n terms.
(Hint: This is an expression in terms of n).
1 answer