What is the sum of 1 + 2 + 3 + ... n ? - Vidyadip

MCQ

What is the sum of $1 + 2 + 3 + ... n\ ?$

A
$\frac{\text{n+1}}{2}$
B
$\frac{\text{n}}{2}$
✓
$\frac{\text{n}(\text{n+1)}}{2}$
D
$\frac{\text{n}(\text{n+2)}}{2}$

✓

Answer

Correct option: C.

$\frac{\text{n}(\text{n+1)}}{2}$

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