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[22+ 32 + 42 + 52 + 62 + 72 + 82 + 92 + 102 + 112] is equal to

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CCommunity
The given expression:

[22+ 32 + 42 + 52 + 62 + 72 + 82 + 92 + 102 + 112]

= [12 +22+ 32 + 42 + 52 + 62 + 72 + 82 + 92 + 102 + 112] – 1

= The sum of squares of first 11 natural numbers – 1

[We know that, the sum of square(s) of 1st n natural numbers = $(\frac{{n\left( {n + 1} \right)\left( {2n + 1} \right)}}{6})$

Here n = 11]

= The sum of squares of first 11 natural numbers – 1

$(= \frac{{11\left( {11 + 1} \right)\left( {22 + 1} \right)}}{6} - 1)$

= 506 – 1

= 505
0
CCommunity
The given expression:

[22+ 32 + 42 + 52 + 62 + 72 + 82 + 92 + 102 + 112]

= [12 +22+ 32 + 42 + 52 + 62 + 72 + 82 + 92 + 102 + 112] – 1

= The sum of squares of first 11 natural numbers – 1

[We know that, the sum of square(s) of 1st n natural numbers = $(\frac{{n\left( {n + 1} \right)\left( {2n + 1} \right)}}{6})$

Here n = 11]

= The sum of squares of first 11 natural numbers – 1

$(= \frac{{11\left( {11 + 1} \right)\left( {22 + 1} \right)}}{6} - 1)$

= 506 – 1

= 505