The sum of first $n$ natural numbers is
The sum of first $n$ natural numbers is
- A
$n\,(n - 1)$
- B
$\frac{{n\,(n - 1)}}{2}$
- C
$n\,(n + 1)$
- D
$\frac{{n\,(n + 1)}}{2}$
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- [IIT 1998]
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