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See Reese

Algebra Level 1

The \( n^{th} \) term of the series \( 1^2 , ( 1^2 + 2^2 ) , ( 1^2 + 2^2 + 3^2 ) \) , \(\ldots \) is?

\[ n^2 + (n - 1)^2 + (n - 2)^2 \] \[ \frac{ n(n + 1)(2n + 1) }{6} \] \[ \frac{n^2 (n + 1)^2 }{2} \] \[ \frac{ n(n + 1) }{2} \]

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by Sakanksha Deo

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