Question

The sum of 1st n terms of the series
$\frac{ {1}^{2} }{1} + \frac{ {1}^{2} + {2}^{2} }{1 + 2 } + \frac{ {1}^{2} + {2}^{2} + {3}^{2} }{1 + 2 + 3}$
option 1)
$\frac{n + 2}{3}$

option 2)
$\frac{n(n + 2)}{3}$

option 3)
$\frac{n(n - 2)}{3}$

option 4)
$\frac{n(n - 2)}{6}$
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Answer 1

Answer:

such a long question any genius can answer it