The sum of first n odd natural numbers in.
A. 2n – 1 B. 2n + 1 C. $\mathrm{n}^{2}$ D. $\mathrm{n}^{2}$ -1 Answer: Option CShow Answer
Solution(By Apex Team)
1, 3, 5, 7, …….. are n odd numbers
Where a = 1, and d = 2
$\begin{aligned}\therefore S_n&=\frac{n}{2}[2a+(n-1)]\\
&=\frac{n}{2}[2\times1+(n-1)\times2]\\
&=\frac{n}{2}[2+2n-2]\\
&=\frac{n}{2}\times2n\\
&=n^2\end{aligned}$
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