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

User Lbrazier
by
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1 Answer

6 votes

Answer:

T10= -21

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 ....

User Mandela
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