Question

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

Answer 1

Answer:

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 ....