If Sn=n^2+3 then t10=?

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Mathematics

22 September, 21:27

If Sn=n^2+3 then t10=?

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Saul · Answer 1

T10 = - 21

Step-by-step explanation:

If Sn=n^2+3 then t10=?

Sn = n²+5

put n=1, 2

S1 = T1 = (1) ²+5

=1+5 = 6

S2 = n²+5

S2 = (2) ²+5

S2=4+5

S2=9

T2 = S2 - S1

T2 = 9-6

T2=3

T10 = a + (n-1) d

where a = 6, d = - 3, n=10

T10 = 6 + (10-1) * -3

T10=6 + (9) * -3

T10=6 + (-27)

T10=6-27

T10 = - 21

Therefore T10 = - 21 ...