If the sum of n terms of a series is Sn = n (5n – 3), find the nth term and pth term.
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2 Answers
23series is AP since sum is a 2° eqn
find first term by finding S1 , find common difference by using S2 - S1
and then use Tn = a+ (n-1)d
are u trying them ?? or just copying ur assignments here ??
or is it dat ur id is fake?
1Sn = n(5n-3)
Sn = n/2 (10n - 6)
comparing with Sn = n/2 ( 2a + (n-1)d)
d = 10
2a-d = -6
therefore a = 4/2 = 2
hence find nth and pth term