Q2 of 23 Page 1

Attempt any four of the following subquestions:

Find the first two terms of the sequence for which Sn is given below: Sn = n2 (n + 1).

Sn denotes the sum of n terms of the sequence.

Therefore, S1 will give the first term of the sequence.


Putting n = 1 in Sn


Sn = n2(n + 1)


S1 = 12(1 + 1) = 2


S2 will give the sum of the first term and the second term.


Putting n = 2 in Sn


Sn = n2(n + 1)


S2 = 22(2 + 1) = 12


S2 = First term + Second term


12 = 2 + Second term


Second term = 12 - 2 = 10.


Therefore, the first two terms of the sequence are 2 and 10.


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