A = 12 + 32 + 52 + ... + 992
A = 1 + 22 + 32 + 42 + 52 + ... + 992
A = 1 + 2 . ( 3 - 1 ) + 3 . ( 4 - 1 ) + ... + 99 . ( 100 - 1 )
A = ( 2 . 3 + 3 . 4 + ... + 99 . 100 ) - ( 1 + 2 + 3 + ... + 9 )
A = \(\dfrac{99.100.101}{3}\) - \(\dfrac{99.\left(99+1\right)}{2}\)
A = 333 300 - 4950
A = 328350
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