Find the sum of first n terms. - Vidyadip

MCQ

Find the sum of first n terms.

A
$\frac{\text{n}(\text{n}+1)}{2}$
B
$\Big(\frac{\text{n}(\text{n}+1)}{2}\Big)$
C
$\frac{\text{n}(\text{n}+1)(2\text{n}+1)}{6}$
D
$\Big(\frac{\text{n}(\text{n}+1)}{2}\Big)$

✓

Answer

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

solution:

Sum of first n terms = 1+2+3+4+……+n

$\Rightarrow\Big(\frac{\text{n}}{2}\Big)=\text{(a}+\text{b)}=\Big(\frac{\text{n}}{2}\Big)(\text{1}+\text{n})=\frac{\text{n}(\text{n}+1)}{2}.$

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