Find the third term of the sequence { (-1)^n+1 3^n / 2n + 1} , n = 1, 2, 3, …. (15 points)

Question

A) 27/7
B) negative 9/5
C) negative 27/ 7
D) 9/5

Answer 1

really? just plug in n=3

(-1)^4 * 3^3 / 2*3 +1
or maybe
(-1)^4 * 3^3/(2*3+1)