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An Amazing Series

Algebra Level 2

$S=1+2+3+\cdots+(n-1)+n+(n-1)+\ldots+3+2+1$

Find general formula of $S$ .

2{n}^{2}

{n}^{2}

2n

{\left(\dfrac{n}{2}\right)}^{2}

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Excel in math and science

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by Dinesh Nath Goswami

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