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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 C
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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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