Find the nth term of the sequence 3, 6, 10, 15, 21…..
- \(\frac{n(n - 1)}{2}\)
- \(\frac{n(n + 1)}{2}\)
-
\(\frac{(n + 1)(n + 2)}{2}\)
- n(2n + 1)
The correct answer is: 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