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प्रश्न
Find the first two terms of the sequence for which Sn is given below: `S_n=n^2(n+1)`
उत्तर
To find the first term, substitute n = 1 in `S_n=n^2(n+1)`
`=>S_1=1^2(1+1)=1(2)=2`
Now S1 is the sum of the first term itself, which is also the first term. So, the first term = 2
To find the second term, substitute n = 2 in `S_n=n^2(n+1)`
`=>S_2=2^2(2+1)=4(3)=12`
Now S2 is the sum of the first two terms.
the first term + the second term = 12
2 + the second term = 12
the second term = 12 - 2
the second term = 10
So, the first term = 2 and the second term = 10.
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