Find the nth term of the sequence 3, 6, 10, 15, 21…..
-
A.
(frac{n(n – 1)}{2}) -
B.
(frac{n(n + 1)}{2}) -
C.
(frac{(n + 1)(n + 2)}{2}) -
D.
n(2n + 1)
Correct Answer: Option C
Explanation
(frac{(n + 1)(n + 2)}{2})
If n = 1, the expression becomes 3
n = 2, the expression becomes 6
n = 4, the expression becomes 15
n = 5, the expression becomes 21